Image copyright LCC Image caption Opposition judicial officials and a rebel commander were reportedly among the dead

At least 29 people, most of them rebel fighters, have been killed in a bombing near Syria's border with Turkey, activists say.

The attack reportedly occurred during a change of guard at the rebel-controlled Atmeh crossing, in Idlib province.

It was not immediately clear whether the blast was caused by a suicide bomber or a remote-controlled device.

A news agency linked to so-called Islamic State (IS) said a suicide car bombing had targeted a rebel convoy.

But an opposition activist network, the Local Co-ordination Committees, reported that a suitcase filled with explosives had been planted at the scene.

In mid-August, 32 rebels were killed in a suicide attack claimed by IS at the Atmeh crossing, which they use to travel from Idlib, via Turkey, to battle the jihadist group in other parts of north-eastern Syria.

The LCC reported that 30 people had been killed and 40 others wounded in Thursday morning's attack, while the UK-based Syrian Observatory for Human Rights put the death toll at 29.

Photographs and videos purportedly of the aftermath showed the bloodied bodies of more than 20 men, some of them wearing camouflage trousers.

Turkey's deputy prime minister called the attack a "crime against humanity".

The president of the Higher Judicial Council in the rebel-held east of the nearby city of Aleppo, Sheikh Khaled al-Sayyed, its attorney-general Mohammed Faraj, and a field commander of the rebel group Ahrar al-Sham, Husham Khalifa, were among those killed, the LCC said. But most of the victims were Faylaq al-Sham fighters.

The rebel faction is participating in a Turkish-led offensive against IS militants and Kurdish fighters along another stretch of border, 60km (37 miles) to the north-east.

Image copyright Reuters Image caption A Turkish-backed rebel offensive is targeting IS strongholds along another stretch of the border

The rebels - assisted by Turkish warplanes, tanks and artillery - quickly seized the former IS stronghold of Jarablus in late August and are now heading towards Dabiq.

The small town holds great symbolic value to jihadists as it is named in Islamic apocalyptic prophecies as the site of an end-of-times showdown between Muslims and their "Roman" enemies - a term IS has now expanded to include the US and its allies.

BBC Turkey correspondent Mark Lowen says Thursday's attack by IS highlights the danger of the mission - Turkey's biggest offensive in Syria since the country's war began in 2011.

Ankara says it will push on with Operation Euphrates Shield, hoping to create a de facto buffer zone close to its vulnerable border, to where some of the 1.5 million Syrian refugees sheltering in Turkey could return.</s>An explosion in a village in northwestern Syria near the border with Turkey killed at least 29 people including several Turkey-backed opposition fighters, Syrian activists said.

The attack, which was quickly claimed by the Islamic State group, underscored the complex layers of the Syrian conflict, where a civil war between Syrian president Bashar Assad’s forces and the rebels trying to oust him is taking place alongside a militant insurgency and an international war against IS.

Meanwhile, activists in the northern Syrian city of Aleppo said it was calmer yesterday after Syria’s military command announced the night before that it would scale back bombardment of the contested city to allow civilians to leave besieged rebel-held neighbourhoods.

“There were shellings and air raids, but it was less than in previous days,” said activist Bahaa al-Halaby, who was speaking from Aleppo province near the city.

The UK-based Syrian Observatory for Human Rights said that although airstrikes have almost stopped on the besieged eastern rebel-held neighbourhoods of the city, government forces were pushing ahead in their ground offensive.

The Observatory and state media said government forces advanced in Aleppo’s northern neighbourhood of Bustan al-Basha where troops captured a sports complex and a nearby housing compound.

Meanwhile, Mr Assad denied reports that his government is targeting hospitals and civilian infrastructure.

Syrian opposition activists and international relief agencies have said Syrian and Russian warplanes have been hitting hospitals and infrastructure in Aleppo.

Mr Assad told Denmark’s TV2 station that “to say that this is our aim as a government, (that) we give the orders to destroy hospitals or schools or to kill civilians, this is against our interest.”

Still, President Assad said mistakes are sometimes committed by individuals in any war.

In the explosion in the village of Atmeh at the Turkish border, activists said the blast occurred as opposition fighters gathered near a small restaurant in the area. It also apparently happened during an exchange of forces going to Syria and some planning to return to Turkey.

The blast was caused by a suicide bomber wearing an explosive belt.</s>At least 29 people, all believed to be rebels, were killed and around 20 others wounded in an explosion near Syria's border with Turkey on Thursday, Al Jazeera reported. The Islamic State group claimed responsibility for the attack.

The Syrian Observatory for Human Rights, a British monitoring group, said the blast took place during change of guard at the rebel-controlled Atmeh crossing. Officials are verifying whether the explosion was triggered by a suicide bomber or a device. Syria-based Local Coordination Committees said the blast was triggered by a explosives-laden bag planted near the border.

The fatalities included the head of the top civil judicial body in rebel-held eastern Aleppo, Sheikh Khaled al-Sayyed, and a judge who worked with him, according to Reuters. A witness said that a majority of the deceased were associated with the Failaq al-Sham group, which has been collaborating with Turkish-backed factions known as the "Euphrates Shield". The Turkish government told BBC that it will continue its offensive, with the aim to create a de facto buffer zone close to its vulnerable border.

The Islamic State group considers Atmeh a priority location because Islamic prophecies say it is the site of an end-of-times battle between Muslims and their "Roman rivals" – a term the extremist group has now expanded to include the Unite States and its allies, BBC reported.

In August, at least 32 rebels were killed in an Islamic State group-planned blast at the Atmeh crossing. Rebels use the point to travel from Syria's Idlib via Turkey to challenge the terror outfit. More than three lakh people have died in the six-year-long civil war in Syria, and nearly half the country's population was forced to flee since it began. While the US supports rebel groups, Russia is seen as a key ally of Syrian President Bashar al-Assad.</s>BEIRUT — An explosion in a village in northwestern Syria near the border with Turkey killed at least 29 people on Thursday, including several Turkey-backed opposition fighters, Syrian activists said. The attack was quickly claimed by the Islamic State group.

The deadly bombing underscored the complex layers of the Syrian conflict, where a civil war between Syrian President Bashar Assad's forces and the rebels trying to oust him is taking place alongside a militant insurgency and an international war against the Islamic State group.

Meanwhile, activists in the northern city of Aleppo said it was calmer on Thursday after Syria's military command announced the night before it would scale back bombardment of the contested city to allow civilians to leave besieged rebel-held neighborhoods.

"There were shellings and air raids, but it was less than in previous days," said activist Bahaa al-Halaby, speaking from Aleppo province near the city.

The Britain-based Syrian Observatory for Human Rights said that although airstrikes have almost stopped on the besieged eastern rebel-held neighbohroods of the city, government forces were pushing ahead in their ground offensive. The Observatory and state media said government forces advanced in Aleppo's northern neighborhood of Bustan al-Basha where troops captured a sports complex and a nearby housing compound.

Meanwhile, Assad denied reports that his government is targeting hospitals and civilian infrastructure. Syrian opposition activists and international relief agencies have said Syrian and Russian warplanes have been hitting hospitals and infrastructure in Aleppo, which has been the epicenter of the Syrian civil war in recent months.

Assad told Denmark's TV2 station that "to say that this is our aim as a government, (that) we give the orders to destroy hospitals or schools or to kill civilians, this is against our interest."

Still, Assad said mistakes are sometimes committed by individuals in any war. Excerpts from the interview were released by Assad's office on Thursday while a full version is to be aired later.

Assad also said that, had his government been "committing all these atrocities," he could not have remained president.

In the explosion in the village of Atmeh at the Turkish border, activists said the blast occurred as opposition fighters gathered near a small restaurant in the area. It also happened during an exchange of forces going to Syria and some planning to return to Turkey, according to Rami Abdurrahman of the Britain-based Syrian Observatory for Human Rights.

The Observatory said the blast in Atmeh was caused by a suicide bomber wearing an explosive belt. The activist group, which tracks the conflict through a network of activists on the ground, said tat along with 29 killed, many others were wounded in the explosion.

Another group, the Local Coordination Committees, said the blast was caused by a bag filled with explosives that went off on the Syrian side of a border crossing, killing 35 people including two senior judicial officials from the opposition.

The Observatory said the dead were Turkish-backed opposition fighters who have been fighting along with Turkish groups against the Islamic State group since August.

An amateur video posted online shows about 18 dead men lying on the floor outside what appears to be a clinic. Some of the men are in military uniforms. The video appears genuine and corresponds to other AP reporting of events depicted.

In the Islamic State group's claim, the IS-linked Aamaq news agency said a suicide car bomber struck a convoy of rebels on the Syrian side of a border crossing point in Atmeh.

Turkish Deputy Prime Minister Numan Kurtulmus described the blast as an "inhuman attack," adding that "those who perpetrated this committed a crime against humanity."

Turkish state-run Anadolu Agency said the attack occurred during a "change of guard" by the Turkish-backed forces at a refugee settlement.

Turkey sent tanks into Syria on Aug. 24 as part of the so-called Euphrates Shield operation aimed at ousting Islamic State fighters and halting an advance by Syrian Kurdish forces, which Ankara sees as allies of Turkey's own outlawed Kurdish militia that has been waging a 30-year insurgency inside Turkey.

In mid August, IS claimed responsibility for a suicide bombing that struck a bus transporting rebels through the Atmeh border crossing between Syria's opposition-held Idlib province and Turkey, killing more than 30 fighters.

The Atmeh border post is one of several crossings Syrian rebels use to bring in fighters and supplies.

Associated Press writer Suzan Fraser contributed to this report from Ankara, Turkey.</s>IS claims bombing of Syrian rebels near Turkey that killed 20

BEIRUT — The Islamic State group has claimed responsibility for a deadly bombing in a northwestern Syrian village that killed at least 20 people, including many Turkey-backed opposition fighters.

The IS-linked Aamaq news agency says a suicide car bomber struck a convoy of rebels on the Syrian side of a border crossing point in the village of Atmeh.

The Britain-based Syrian Observatory for Human Rights said the blast killed at least 20 people and wounded dozens. An activist collective in Idlib province known as Ariha Today put the death toll at 24.

The Observatory says the killed rebels have been fighting along with Turkish forces against the Islamic State group since August.</s>BEIRUT — The Latest on developments in Syria (all times local):

The Islamic State group has claimed responsibility for a deadly bombing in a northwestern Syrian village that killed at least 20 people, including many Turkey-backed opposition fighters.

The IS-linked Aamaq news agency says a suicide car bomber struck a convoy of rebels on the Syrian side of a border crossing point in the village of Atmeh.

The Britain-based Syrian Observatory for Human Rights said the blast killed at least 20 people and wounded dozens. An activist collective in Idlib province known as Ariha Today put the death toll at 24.

Syrian activists have raised the death toll from an explosion in a northwestern village near the border with Turkey to at least 20 killed, including Turkey-backed rebels.

The Britain-based Syrian Observatory for Human Rights says the blast in Atmeh on Thursday morning was either caused by a suicide bomber or a remotely detonated bomb. Another group, the Local Coordination Committees, says the blast was caused by a bag filled with explosives that went off on the Syrian side of a border crossing.

An activist collective in Idlib province known as Ariha Today says the blast killed 24.

The Observatory says the killed rebels have been fighting along with Turkish forces against the Islamic State group since August.

No one claimed responsibility for the attack.
A bombing in rebel controlled Atme, Idlib Governorate, near the Syria–Turkey border, kills at least 29 people, mostly rebel fighters, and injures dozens more. ISIL claims responsibility.