After 4 days, Egypt claims Israel-Gaza ceasefire Updated 9:10 p.m. (CBS/AP) GAZA CITY, Gaza Strip - An Egyptian security official says his country has mediated a cease-fire between Palestinian militant factions and Israel after four days of violence. The official told The Associated Press that a cease-fire had gone into affect at 1 a.m. Tuesday local time. He was speaking on condition of anonymity because of the sensitivity of the issue. It was not immediately clear when a formal announcement would be made. He said that after hours of talks, the Palestinians agreed to stop launching rockets at southern Israeli cities and Israel agreed to stop targeting militants in airstrikes. Neither Palestinian militant groups or Israel would immediately comment. There were no reports of violence by either side. Gaza's Hamas rulers have been careful to stay on the sidelines. Islamic Jihad - now closer to Iran than is its larger rival Hamas - had taken the lead in this round of fighting against Israel. These are some of the trends emerging from four days of fighting between Israel's air force and Gaza rocket squads, triggered by Israel's killing of a militant leader last week. Twenty-four Palestinians have been killed, including seven on Monday, and about 1 million Israelis in rocket range have seen their lives disrupted by the threat of rocket attacks, with frequent sirens warning them to run for cover. 5 killed as Israel continues strikes on Gaza Gaza-Israel border fighting reaches third day A rocket is launched from the Israeli anti-missile system known as Iron Dome in order to intercept a rocket fired by Palestinian militants from the Gaza Strip in Ashdod, Israel, Sunday, March 11, 2012. In Israel, government officials and missile experts praised the performance of Iron Dome, an Israeli-made system designed to shoot down short-range rockets like those fired from Gaza. Iron Dome has been rolled out over the past year, and the recent fighting posed its most serious test. Israel has other systems deployed against longer-range missiles. Iron Dome uses cameras and radar to track incoming rockets and intercepts only those that would pose a threat to people and property, ignoring those that are expected to fall in open areas. The military said that of 143 rockets fired since Friday, it tried to intercept 63 and succeeded in all but nine of those attempts. No Israelis have been killed in the current fighting, and property damage has been relatively minor. Uzi Rubin, a missile expert and former Defense Ministry official, said Iron Dome has exceeded expectations. "The performance up to now has been almost flawless," Rubin said, adding that the perception could change quickly in the event of casualties. Some noted that each intercept costs about $100,000, arguing that the cost could be prohibitive if Israel were fighting a full-fledged war. In the current round, Islamic Jihad, the second largest militant group in Gaza, has taken the initiative. Islamic Jihad has maintained close ties to its sole sponsor, Iran, while Hamas in recent months has drifted away from its longtime patron, in part because of disagreements over Syria's brutal crackdown on regime opponents. Iran has punished Hamas for refusing to side with Syrian President Bashar Assad, including by cutting funding. Israeli officials believe that Islamic Jihad has amassed hundreds of rockets and missiles, if not thousands, including weapons taken from Libyan military bases during the chaos surrounding the fall of Libya's longtime ruler, Muammar Qaddafi. Missiles and other weapons reach Gaza through smuggling tunnels running under its border with Egypt. In the current round, Islamic Jihad showed that the three main cities in southern Israel - Ashkelon, Ashdod and Beersheba - are in easy reach of its Russian-designed Grad rockets. On Monday, two dozen rockets struck southern Israel, including one that damaged an empty preschool on a communal farm. Police said no one was hurt. Rubin believes Islamic Jihad also has longer-range missiles that could reach the major population centers of central Israel, like Tel Aviv. Hinting at possible escalation, Islamic Jihad warned Monday that its "patience is limited" and that it is ready to unleash "fire and destruction," though such rhetoric is routine during flare-ups like this one. Hamas, which has ruled Gaza since a 2007 takeover, has pointedly kept out of the fighting and is appealing for calm, though it has not prevented rocket fire by Islamic Jihad and the Popular Resistance Committees. Hamas is trying not to provoke a major Israeli offensive that could undermine its control of the territory of 1.7 million Palestinians. An Israeli offensive three years ago delivered a damaging blow. "Hamas is behaving like a responsible government in Gaza," said Fawaz Gerges of the London School of Economics. On Monday, four militants, a 16-year-old, a 65-year-old man and the man's 30-year-old daughter were killed in four separate raids, Gaza health official Adham Abu Salmia said. The teenager died while walking to school, and the father and daughter were killed when a missile struck outside their home, witnesses said. Two dozen Palestinians, including several children, were wounded in a separate pre-dawn strike. Israel said the raid targeted munitions stores in a residential building. In Israel, thousands spent another day in bomb shelters, while others ran for cover when sirens wailed. Some 200,000 students were kept home from schools for a second day. The Maariv daily ran a front page picture of a 10-year-old girl from Beersheba, shown lying on a street with her hands over her head. She later explained that a siren had just gone off, and she dropped to the ground because she didn't have anywhere to run.