Jerusalem (CNN) In the most serious clash between Israeli and Syrian forces since the start of the Syrian conflict six year ago, Israeli aircraft struck several targets in Syria overnight, the Israeli military said Friday.

Israel targeted a military site near the ancient city of Palmyra , the Syrian military said,in what would be one of its deepest airstrikes inside Syrian territory since the civil war began there.

Palmyra, once held by ISIS and retaken by the Syrian government, is strategically important to both the regime and its opponents.

Most of Israel's reported strikes have been around the capital of Damascus, about 60 kilometers (37 miles) from the Israeli-occupied Golan Heights

In response, Syrian forces fired anti-aircraft missiles at the Israeli jets, saying they downed one aircraft and hit another. Israeli vehemently denied the assertions, calling them "absolutely not true."

🔴 Overnight, IAF conducted strikes against several targets in #Syria. Anti-aircraft missiles launched at the aircraft were intercepted. — Peter Lerner (@LTCPeterLerner) March 17, 2017

"At no point was the safety of Israeli civilians or the IAF aircraft compromised," a statement from the Israel Defense Forces said. The statement is unusual in that Israel rarely comments on airstrikes in Syria.

The intercept triggered alarm sirens in the Jordan Valley. Shrapnel from the explosion, which was heard as far south as Jerusalem, landed in western Jordan, the Jordanian military said.

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Syria's latest claims are reminiscent of its statement in September about downing an Israeli aircraft near Quneitra, close to the Golan Heights. Israel seized parts of that region from Syria in the 1967 Six Day War

The Israeli military said then that Syria fired two anti-aircraft missiles at its jets targeting artillery positions, but both missiles missed. They were fired long after Israeli jets left the area, the military added.

Arrow missile defense

One of the missiles overnight was intercepted by Israel's Arrow missile defense system , marking its first operational use. Arrow, Israel's ballistic missile defense system and the long-range version of its Iron Dome , is designed to intercept missiles outside the atmosphere.

The use came more than a year after the first successful Arrow-3 intercept test was carried out in December 2015. At that time, Israeli officials would not say when the missile would become operational.

The Israeli military would not explain why Arrow was used against an anti-aircraft missile, fueling speculation that Israel was either testing the Arrow missile or that its Iron Dome missile defense system wasn't within range of downing the anti-aircraft missile.

Taking aim at weapons smuggling

Israel has long focused on stopping the transfer of weapons from Syria to terror groups.

In December, Israeli Defense Minister Avigdor Liberman told a delegation of European Union envoys that Israel will "prevent the smuggling of sophisticated weapons, military equipment and weapons of mass destruction from Syria to Hezbollah."

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It was another acknowledgement of Israel's ongoing operations in Syria. Last April, Prime Minister Benjamin Netanyahu confirmed that Israel has struck Syria "dozens of times," breaking with the policy of remaining quiet about involvement in its war-torn northern neighbor.

Netanyahu returned last week from Moscow, where he reaffirmed Israel's military coordination with Russia in the skies over Syria. The two countries established the coordination last year to avoid conflicts in Syrian airspace, ostensibly to allow both countries to operate freely. Netanyahu also expressed his concerns about a growing Iranian presence in Syria.

Repeated incursions

Israel has attempted to stay out of Syria's civil war but has reportedly struck the country multiple times in the past, often taking aim at weapons shipments intended for Hezbollah in Lebanon.

As recently as late February, Syrian media reported that Israeli jets hit military positions and weapons convoys near Damascus.

In November 2012, Israel fired warning shots toward Syria after a mortar shell hit an Israeli military post, the first time Israel had fired on Syria across the Golan Heights since the 1973 Yom Kippur War

Israeli jets have been hitting targets in Syria since at least 2013, when US officials told CNN they believed IDF jets had struck nside Syrian territory.

In 2014, the Syrian government and an opposition group both said an IDF strike had hit Damascus' suburbs and airport

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The state-run Syrian Arab News Agency characterized those strikes as "a flagrant attack on Syria, targeting two safe areas in (the) Damascus countryside in Dimas and near Damascus International Airport."

Israeli strikes have also gone after ISIS fighters inside Syria. Late last year, IDF troops operating in the disputed Golan region came under fire from militants of the ISIS affiliate Khalid ibn al-Walid Army, Israeli military spokesman Lt. Col. Peter Lerner said.</s>Al-jineh: The US said it carried out an air strike in Syria against an al-Qaeda meeting but denied deliberately targeting a mosque where a monitor said on Friday 46 people were killed.

The Syrian Observatory for Human Rights said most of the dead in the Thursday evening raid on Al-Jineh, in the northern province of Aleppo, were civilians.

The US-led coalition has been bombing jihadist groups in war-torn Syria since 2014, with hundreds of civilians unintentionally killed in the country and in neighbouring Iraq.

"We did not target a mosque, but the building that we did target -- which was where the meeting took place -- is about 50 feet (15 metres) from a mosque that is still standing," said Colonel John J. Thomas, spokesman for US Central Command.

According to a Centcom statement: "US forces conducted an air strike on an Al-Qaeda in Syria meeting location March 16 in Idlib, Syria, killing several terrorists."

The Centcom spokesman later clarified that the precise location of the strike was unclear -- but that it was the same one widely reported to have hit the village mosque in Al-Jineh, in Aleppo province.

"We are going to look into any allegations of civilian casualties in relation to this strike," he added. An AFP correspondent saw rescue workers in white helmets working under spotlights with picks and shovels late on Thursday to dig people out of the rubble.

Much of the building, identified by a black placard outside as a mosque, had been flattened. The empty prayer hall was covered in debris, and rescue workers stepped through it carefully, deliberating how to break down a wall to search for more survivors.

Rescuers had earlier left the wreckage site but were forced to double back when they heard moaning coming from the rubble. "More than 100 people were wounded," Observatory head Rami Abdel Rahman said on Thursday, adding that many were still trapped under the collapsed mosque in the village of Al-Jineh, just over 30 kilometres (20 miles) west of Aleppo.

The village is held by Islamist groups, but the Observatory said no jihadist factions are present. Abu Muhammed, a village resident, told AFP that he "heard powerful explosions when the mosque was hit. It was right after prayers at a time when there are usually religious lessons for men in it.

"I saw 15 bodies and lots of body parts in the debris when I arrived. We couldn't even recognise some of the bodies," he added. More than 320,000 people have been killed in Syria since the conflict began with anti-government protests six years ago.

A ceasefire between government forces and non-jihadist rebel groups was brokered by rebel backer Turkey and regime ally Russia in December, but violence has continued.

The Observatory, which relies on a network of sources inside Syria for its information, says it determines whose planes carry out raids according to type, location, flight patterns and munitions used.

But the skies over Aleppo province are busy, with Syrian regime and Russian warplanes as well as US-led coalition aircraft carrying out strikes.

Russia began a military intervention in Syria in September 2015, and in the past has dismissed allegations of civilian deaths in its strikes. The US-led coalition fighting the Islamic State group said earlier this month that its raids in Iraq and Syria had unintentionally killed at least 220 civilians since 2014.

Critics say the real number is much higher. Israel has also carried out air strikes elsewhere in Syria. Before dawn on Friday, its warplanes hit several targets near the famed desert city of Palmyra, prompting retaliatory missiles launches, in the most serious incident between the two countries since the Syrian civil war started in 2011.

The Syrian army said it had downed one Israeli plane and hit another but the Israeli military insisted the safety of its aircraft had not been compromised.

Israel said it intercepted one missile. Jordanian military sources said missile shrapnel struck in the north of the kingdom without causing any casualties.</s>Syria and Israel engaged in the most serious incident between the two countries since the outbreak of the Syrian civil war six years ago overnight on Thursday, as Israeli Air Force Planes struck several targets in Syria.

The General Command of the Army and the Armed Forced announced on Friday that the Syrian air defense downed one of four Israeli warplanes that violated the Syrian airspace and targeted a military site in the eastern countryside of Homs.

According to a statement by the Command, the four Israeli aircrafts violated the Syrian airspace in al-Breij area through the Lebanese territories at 2:40 am.

The Israeli warplanes targeted a military site near Palmyra in the eastern countryside of Homs, said the Army’s Command, confirming that the Syria air defense forces confronted the enemy’s aircrafts and shot down one of them inside the occupied territories, hit another and forced the other two to withdraw.

The Israeli army said that none of the missiles struck the jets, though in Syria, the military claimed Friday that one Israeli jet had been shot down and another damaged.

The Israeli army said the rocket fired toward Israel was not among Syria’s most advanced and the incident was the first confirmed instance of operational use of the Arrow system – meant to challenge the threat of ballistic missiles – despite being first delivered to the army in the late 90s.

According to the Israeli army, the aircraft had already returned to Israeli airspace when Syrian launched its air-defense rockets.

There were no Israeli casualties in the incident, and the IOF military spokesperson’s unit confirmed Israel struck targets in Syria in an exceptionally rare statement.

There have been several reports over the past five years that Israel has targeted weapons convoys in Syria headed for Hezbollah in Lebanon, but until now Israel has not officially addressed these claims.

Earlier in the night, the IOF confirmed sirens sounded in the Jordan Valley in eastern Israel.

Less than a month ago, on February 22, Lebanese reports indicated that Israeli forces had struck an arms convoy outside of Damascus in an attacked carried out from Lebanese airspace.

One month before that, on January 13, the Syrian government warned of repercussions to what it called a “flagrant” attack after the army told state media that Israeli missiles had struck a military airport west of Damascus.</s>JERUSALEM — Syria fired missiles at Israeli warplanes early Friday after a series of Israeli airstrikes inside Syria — a rare military exchange between the two hostile neighbors that was confirmed by both sides.

The Israeli military said its aircraft struck several targets in Syria and were back in Israeli-controlled airspace when several anti-aircraft missiles were launched from Syria toward the Israeli jets.

Israeli aerial defense systems intercepted one of the missiles, the army said, without elaborating. It would not say whether any other missiles struck Israeli-held territory, but said the safety of Israeli civilians and Israeli aircraft was “not compromised.” (Washington Post)

All sorts of wild rumors were flying about after this exchange this morning. Most of them, if not all of them, are not true. Even the U.S. is downplaying the whole affair. A DOD spokesman said this in a briefing. "I do not have any particular reaction for you. We are certainly aware of it. This is a matter between Israel and Syria and not something we were a party to.”

The best explanation I’ve seen for this is offered by Elijah J. Magnier over his twitter account.

1. What happen between Israel and Syria today in Palmyra?

Israel tried to break "redlines", attacking inside the "allowed zones & targets.

2. There are no targets for Iran or Hezbollah (weapons traveling to Lebanon or the Golan heights) in Palmyra but an attempt to push ROE.

3. The targets Israel hit today are close to the T4 and are involved in the war in Syria, a red line for Russia who approved a "warning"

4. Russia doesn't want to see an Israeli jet hit over its operational theatre (in Syria) unless Israel pushed the boundaries.

5. This explains why Syria didn't use its S-300 but limited itself to already existing anti-air missiles and a "warning to Israel".

6. As long as Israel hits targets in Damascus airport or warehouses on the way to Lebanon (not inland like today) Russia won't intervene.

7. The recent visit of Netanyahu to Moscow failed to reach its objectives in convincing Russia to switch against Iran and Hezbollah.

8. Israel tried to "test the ground" today but will "close the incident" and accept the message behind it, aware Syria is Russia’s playground. (@EjmAlrai)

I agree with Magnier. If Bibi didn’t receive the message during his pilgrimage to Moscow last week, I would think he got it loud and clear this morning. Vladimir Vladimirovich is calling the shots now in this part of the Mediterranean... and he wants a quiet, orderly neighborhood.</s>Israel has denied a claim by Syria that it shot down an Israeli plane carrying out pre-dawn raids on a military target near Palmyra (AFP Photo/)

Jerusalem (AFP) - Israeli warplanes struck several targets in Syria early Friday, prompting retaliatory missiles launches, in the most serious incident between the two countries since the Syrian civil war began six years ago.

Syria's military said it had downed an Israeli plane and hit another as they were carrying out pre-dawn strikes near the famed desert city of Palmyra that it recaptured from jihadists this month.

"Our air defence engaged them and shot down one warplane over occupied territory, hit another one, and forced the rest to flee," the army said in a statement carried by state news agency SANA.

The Israeli army denied any planes had been struck and the Syrian government has made similar unfounded claims in the past.

"The safety of Israeli civilians or the Israeli air force aircraft was at no point compromised," army spokesman Peter Lerner told AFP.

The Israeli air force said earlier that it had carried out several strikes on Syria overnight, but that none of the ground-to-air missiles fired by Syrian forces in response had hit Israeli aircraft.

It was an unusual confirmation by the Jewish state of air raids inside Syria.

"Overnight... aircraft targeted several targets in Syria," an Israeli army statement said.

"Several anti-aircraft missiles were launched from Syria following the mission and (army) aerial defence systems intercepted one of the missiles."

None of the missiles fired from Syria hit their targets, the army added.

One missile was intercepted north of Jerusalem by Israel's Arrow air defence system, Israeli media reported.

It would be one of the first times the system has been used.

A Jordanian military source said shrapnel from one missile struck in the north of the kingdom without causing any casualties.

Both Israeli and foreign media have reported a number of Israeli air strikes inside Syria targeting arms convoys of Lebanese militant group Hezbollah, which fought a devastating 2006 war with Israel and is now fighting alongside the Damascus regime.

The Jewish state does not usually confirm or deny each raid but may have been led to do so this time by the circumstances of the incident.

The missile fire prompted air raid sirens to go off in the Jordan Valley during the night, the Israeli army said.

In April 2016, Prime Minister Benjamin Netanyahu admitted for the first time that Israel had attacked dozens of convoys transporting weapons in Syria destined for Hezbollah.

Israel and Syria are still technically at war, though the border had remained largely quiet for decades until 2011 when the Syrian conflict broke out.

Iranian-backed Hezbollah has been fighting inside Syria in support of President Bashar al-Assad against the rebels.

While there has been periodic stray fire into the Israeli-occupied Golan Heights that has prompted retaliatory strikes, Israel has largely avoided getting sucked into the conflict directly.

Witnesses cited by the press also reported two explosions that could have been caused by the launch of the anti-missile system.

The Arrow 3 interceptor, designed to shoot down ballistic missiles, was handed to air force bases in Israel in January after successful testing by Israel and the United States.

Israel seized most of the Golan Hights from Syria in the Six-Day War of 1967 and annexed it in 1981 in a move never recognised by the international community.

Israel pays close attention to developments in the Syrian conflict for fear that it could be exploited by its arch-rival Iran to install allies close to the armistice line on the Golan and Israel's borders.

In the summer of 2006, Israel and Hezbollah fought a devastating war that killed nearly 1,200 people in Lebanon, most of them civilians, and about 160 Israelis, most of them troops.</s>Jerusalem (CNN) In the most serious clash between Israeli and Syrian forces since the start of the Syrian conflict six year ago, Israeli aircraft struck several targets in Syria overnight, the Israeli military said Friday.

Israel targeted a military site near the ancient city of Palmyra , the Syrian military said,in what would be one of its deepest airstrikes inside Syrian territory since the civil war began there.

Palmyra, once held by ISIS and retaken by the Syrian government, is strategically important to both the regime and its opponents.

Most of Israel's reported strikes have been around the capital of Damascus, about 60 kilometers (37 miles) from the Israeli-occupied Golan Heights

In response, Syrian forces fired anti-aircraft missiles at the Israeli jets, saying they downed one aircraft and hit another. Israeli vehemently denied the assertions, calling them "absolutely not true."

"At no point was the safety of Israeli civilians or the IAF aircraft compromised," a statement from the Israel Defense Forces said. The statement is unusual in that Israel rarely comments on airstrikes in Syria.

The intercept triggered alarm sirens in the Jordan Valley. Shrapnel from the explosion, which was heard as far south as Jerusalem, landed in western Jordan, the Jordanian military said.

The Israeli military said then that Syria fired two anti-aircraft missiles at its jets targeting artillery positions, but both missiles missed. They were fired long after Israeli jets left the area, the military added.

The use came more than a year after the first successful Arrow-3 intercept test was carried out in December 2015. At that time, Israeli officials would not say when the missile would become operational.

The Israeli military would not explain why Arrow was used against an anti-aircraft missile, fueling speculation that Israel was either testing the Arrow missile or that its Iron Dome missile defense system wasn't within range of downing the anti-aircraft missile.

Israel has long focused on stopping the transfer of weapons from Syria to terror groups.

It was another acknowledgement of Israel's ongoing operations in Syria. Last April, Prime Minister Benjamin Netanyahu confirmed that Israel has struck Syria "dozens of times," breaking with the policy of remaining quiet about involvement in its war-torn northern neighbor.

Israel has attempted to stay out of Syria's civil war but has reportedly struck the country multiple times in the past, often taking aim at weapons shipments intended for Hezbollah in Lebanon.

As recently as late February, Syrian media reported that Israeli jets hit military positions and weapons convoys near Damascus.

The state-run Syrian Arab News Agency characterized those strikes as "a flagrant attack on Syria, targeting two safe areas in (the) Damascus countryside in Dimas and near Damascus International Airport."

Israeli strikes have also gone after ISIS fighters inside Syria. Late last year, IDF troops operating in the disputed Golan region came under fire from militants of the ISIS affiliate Khalid ibn al-Walid Army, Israeli military spokesman Lt. Col. Peter Lerner said.</s>An Israeli fighter jet was downed by Syrian anti-aircraft systems as a squadron of warplanes violated the Syrian airspace.

“At 2:40 a.m. this morning, a squadron of four Israeli warplanes violated the Syrian airspace through Lebanon near Al-Bureij area, and targeted an Army position near Palmyra in Homs eastern countryside,” said the official statement issued by the Syrian Army’s General Command.

“The Syrian Army’s air defence systems responded and managed to shoot down a fighter jet, damage another one, thus forcing them to withdraw,” the statement continued.

The escalation was also reported by Avijaa Adraei, spokesman of the Israeli Army, who tweeted that “while targeting several objectives in Syria, the Israeli warplanes were targeted by anti-aircraft missiles fired by the Syrian Army.”

Adraei pointed out that one of the missiles was intercepted by the Iron Dome and crashed in an area to the north of Jerusalem.

Israeli fighter jets have conducted several airstrikes inside the Syrian territories during the Syrian war. The airstrikes killed several prominent anti-Israeli figures from both Hezbollah and the Syrian resistance, and destroyed weapons destined for Hezbollah according to Israeli claims.</s>The Syrian army said Israeli jets breached the war torn country’s airspace in the early hours of Friday morning and attacked a “military target” near Palmyra.

The jets were then reportedly targeted by Syrian anti-aircraft missiles.

According to a statement from the Syrian Army, a total of four Israeli jets breached Syrian airspace on Friday morning. Syria’s air defenses shot down one of the jets over “occupied ground” and damaged another.

The Israeli Army confirmed it had conducted airstrikes on several targets in Syria, but the IDF claim that none of the jets were damaged.

Israeli warplanes “penetrated our airspace at 2:40 a.m. (0040 GMT) via Lebanese territory and hit a military target on the way to Palmyra,” said an army statement carried by state news agency SANA.

“Our air defense engaged them and shot down one warplane over occupied territory, hit another one, and forced the rest to flee,” the army said, apparently referring to the Golan Heights.

The Syrian army also slammed Tel Aviv’s strikes as “an act of aggression” meant to assist the Takfiri Daesh terror group.

Israel’s aerial assaults are “a desperate attempt to raise their (Daesh terrorists’) deteriorating morale and divert attention away from the victories which Syrian Arab Army is making in the face of the terrorist organizations,” the statement read.

 The Syrian army recaptured Palmyra from Daesh on March 2. In January, the army accused Israel of carrying out missile strikes on the Mazzeh air base near Damascus.

The Syria army underlined its resolve to repel any future Israeli attack by “all possible means.”

Israel has carried out air raids against Syrian-based targets on many occasions, but it rarely acknowledges the attacks. On Friday, however, the Israeli military acknowledged that its jets bombed several targets in Syria.

In a statement, the military said the Syrian air force fired numerous anti-aircraft missiles at the warplanes and the Israeli air force “intercepted one of the missiles.”

The explosion caused by the incident set off sirens in the Jordan Valley of the West Bank and the blast was heard as far as Jerusalem al-Quds, according to the Israeli military statement.

The Israeli military later said in a separate statement that its aircraft were unharmed in the operation.

Israel and Syria are technically at war due to Tel Aviv’s continued occupation of the latter’s Golan Heights since 1967. Tel Aviv has also been supporting the militants operating to topple the Syrian government.

Some of the attacks have reportedly struck targets belonging to the Lebanese resistance movement of Hezbollah, which has been assisting the Syrian military in the face of the militancy.</s>JERUSALEM (AP) — Syria fired missiles at Israeli warplanes early Friday after a series of Israeli airstrikes inside Syria — a rare military exchange between the two hostile neighbors that was confirmed by both sides.

The Israeli military said its aircraft struck several targets in Syria and were back in Israeli-controlled airspace when several anti-aircraft missiles were launched from Syria toward the Israeli jets.

Israeli aerial defense systems intercepted one of the missiles, the army said, without elaborating. It would not say whether any other missiles struck Israeli-held territory, but said the safety of Israeli civilians and Israeli aircraft was “not compromised.”

The army said the incident set off sirens in Jewish settlement communities in the Jordan Valley, part of the West Bank.

The firing of missiles from Syria toward Israeli aircraft is extremely rare, though Israeli military officials reported a shoulder-fired missile a few months ago.

A Syrian military statement said four Israeli warplanes violated Syrian airspace — flying into Syria through Lebanese territory — and targeted a military position in central Syria.

Damascus said Syrian anti-aircraft systems confronted the planes and claimed one of the jets was shot down in Israeli- controlled territory and that another was hit. The Israeli military denied the allegation and there was no sign that any of the jets had been hit or downed.

The Syrian statement, in line with typical anti-Western rhetoric from Damascus, said the “blatant aggression” was an attempt by Israel to support “terrorist gangs” of the Islamic State group inside Syria and “deflect from the victories” of the Syrian army in the country’s civil war, which this week entered its seventh year.

Israeli Channel 10 TV reported that Israel deployed its Arrow defense system for the first time against a real threat and hit an incoming missile, intercepting it before it exploded in Israel.

The station said the Israeli military had been on a mission to destroy a weapons convoy destined for the Lebanese Hezbollah group, which is backed by Iran and fights alongside Syrian government forces.

There was no immediate comment from Hezbollah.

Jordan, which borders both Israel and Syria, said parts of the missiles fell in its rural northern areas, including the Irbid district. The military said the debris was the result of the Israeli interception of missiles fired from Syria toward Israeli positions and bases.

Radwan Otoum, the Irbid governor, told the state news agency Petra that the missile parts caused only minor damage.

A chunk of missile crashed into the courtyard of a home in the community of Inbeh in northern Jordan, about 40 kilometers (25 miles) from the Syrian border.

Umm Bilal al-Khatib, a local resident, said she heard an explosion and initially thought a gas cylinder had exploded. When she went outside she found a small crater and a 3-meter-long (10-foot) cylinder. She said her husband contacted Jordanian authorities, who removed the debris.

The Haaretz daily said the interception took place north of Jerusalem. However, the Arrow is designed to intercept long-range ballistic missiles high in the stratosphere, so it remained unclear why the system would have been used in this particular incident.

The Israeli military had no immediate comment on the reports.

The Arrow is part of what Israel calls its “multilayer missile defense” comprised of different systems meant to protect against short and long-range threats, including the thousands of missiles possessed by Hezbollah in Lebanon and rockets used by Hamas and other Islamic militant groups in Gaza.

Israel has been largely unaffected by the Syrian civil war raging next door, suffering mostly sporadic incidents of spillover fire that Israel has generally dismissed as tactical errors by Syrian President Bashar Assad’s forces. Israel has responded with limited reprisals on Syrian positions in response to the errant fire.

The Syrian conflict, which began in March 2011 as a popular uprising against Assad, eventually descended into a full-blown civil war with Syrian government forces fighting an array of rebel groups. The chaos has allowed al-Qaida’s affiliate in Syria and the Islamic State group to expand their reach.

The skies over Syria are now crowded, with Russian and Syrian aircraft backing Assad’s forces and a U.S.-led coalition striking Islamic State and al-Qaida targets.

Israel is widely believed to have carried out airstrikes on advanced weapons systems in Syria — including Russian-made anti-aircraft missiles and Iranian-made missiles — as well as Hezbollah positions, but it rarely confirms such operations.

Hezbollah is pledged to Israel’s destruction and fought a monthlong war with the Jewish state in 2006.</s>Israeli warplanes struck several targets in Syria early Friday, prompting retaliatory missile launches, in the most serious incident between the two countries since the Syrian civil war began six years ago.

Israeli Prime Minister Benjamin Netanyahu said the strikes targeted weapons bound for Lebanon's Hezbollah, and that the Jewish State would do the same again if necessary.

Syria's military said it had downed an Israeli plane and hit another as they were carrying out pre-dawn strikes near the famed desert city of Palmyra that it recaptured from jihadists this month.

The Israeli military denied that any planes had been hit. The Syrian government has made similar unfounded claims in the past.

"The safety of Israeli civilians or the Israeli air force aircraft was at no point compromised," Israeli army spokesman Peter Lerner told AFP.

Netanyahu said in footage aired on Israel's major television networks: "When we identify attempts to transfer advanced weapons to Hezbollah and we have intelligence and it is operationally feasible, we act to prevent it.

"That's how it was yesterday and that's how we shall continue to act," he added.

"We are fully determined and the evidence of that it that we are acting. Everybody must take that into account -- everybody."

The Israeli air force said earlier that it had carried out several strikes on Syria overnight, but that none of the ground-to-air missiles fired by Syrian forces in response had hit Israeli aircraft.

It was an unusual confirmation by the Jewish state of air raids inside Syria.

"Overnight... aircraft targeted several targets in Syria," an Israeli army statement said.

"Several anti-aircraft missiles were launched from Syria following the mission and (Israeli) aerial defence systems intercepted one of the missiles," it said.

None of the missiles fired from Syria hit their targets, the army added.

One missile was intercepted by Israel's Arrow air defence system, Israeli media reported.

It would be one of the first times the system has been used.

A Jordanian military source said shrapnel from one missile fell in the north of the kingdom without causing any casualties.

In April 2016, Netanyahu admitted for the first time that Israel had attacked dozens of convoys transporting weapons in Syria destined for Hezbollah, which fought a devastating 2006 war with Israel and is now fighting alongside the Damascus regime.

Israel does not usually confirm or deny each individual raid, but it may have been led to do so this time by the circumstances of the incident.

The missile fired from Syria prompted air raid sirens to sound in the Jordan Valley during the night, the Israeli army said.

Israel and Syria are still technically at war, though the border had remained largely quiet for decades until 2011 when the Syrian conflict began.

Assaf Orion, senior research fellow at Israel's Institute for National Security Studies, said Syria's response was a "significant" shift.

Until now, he said, when Israel attacked Hezbollah convoys there, it "usually went without a response or with an insignificant response from the Syrian side".

"(With this attack) the Syrian regime is trying to tell Israel it can't stand it any more and those actions will not be free of charge."

President Bashar al-Assad's position has been strengthened in recent months with his forces reclaiming all of Syria's second city Aleppo, as well as enjoying continuing Russian support.

Orion said the Syrian leader was feeling emboldened.

"He is saying: 'Don´t push me. I am not as weak as I used to be.'"

Yaakov Amidror, a former head of Israel's National Security Council, said weapons convoys of the Iran-backed Hezbollah remained a "red line" and that Israel would continue to attack them when deemed necessary.

The Arrow 3 interceptor, designed to shoot down ballistic missiles, was deployed to Israeli air force ground crews in January after successful testing by Israel and the United States.

Israel seized most of the Golan Heights from Syria in the 1967 Six-Day War and annexed it in 1981, in a move never recognised by the international community.

Israel pays close attention to developments in the Syrian conflict for fear that it could be exploited by its arch-rival Iran to instal allies close to the armistice line on the Golan and Israel's borders.
The Israeli Air Force launches several airstrikes on targets inside Syria, and for the first time, publicly claims responsibility. Syrian air defenses responded by launching missiles at the aircraft, and thereupon Israeli Arrow 3 missiles were launched in response to the counter-offensive. Israel stated that it was targeting suspected weapons shipments to Hezbollah in Lebanon, adding that the Israeli military will keep intervening until they believe such shipments have ceased. According to the Syrian Army, four Israeli jets entered its airspace and struck targets near Palmyra.