Medical sources in Gaza said Raed Abdel Foull, a commander in the Popular Resistance Committees, was killed with his wife by an Israeli missile as they drove in the northern town of Beit Lahiya, bringing to 26 the number of Palestinian civilians and militants killed in less than three days.

The latest strike came as Israeli leaders vowed to keep up their attacks against militancy in Gaza, which Hamas took over by force from the Palestinian Authority, led by Mahmoud Abbas' Fatah movement.

Israeli Prime Minister Ehud Olmert told a conference in Tel Aviv Thursday: "We cannot accept the continuation of fire against our citizens and we will continue to react with intelligence and with the most precision possible to put an end to the terrorist fire, all the while trying to avoid civilian victims."

The Israeli strikes and incursions into Gaza, however, provoked Hamas to fire several dozen rockets into Israel for the first time in months, lightly injuring 10 people. And more of these home-made, inaccurate rockets and mortars landed into southern Israel on Thursday, causing little damage.

While Israel boasts that its superior military technology enables it to hit their targets, a high number of civilians have been killed in the process, which the Palestinians say is deliberate to also "liquidate" the families of the targeted militants.

Hamas, the Palestinian Islamic Resistance Movement, which came to power by an overwhelming victory in legislative elections two years ago, has been isolated in a besieged Gaza as a "terrorist organization" by Israel and the U.S.-led Western world.

On Wednesday, a teenage boy, his father and an uncle were killed by an Israeli missile that hit their car in Gaza City, which Israel said was meant to hit another vehicle driven by Islamic Jihad gunmen.

On the worst single day of hostility Tuesday, 19 Palestinian civilians and activists were killed, including a son of senior Hamas leader Mahmoud Zahar, the second son he has lost to Israeli fire.

Palestinian President Mahmoud Abbas, who has refused to communicate with Hamas since being ousted from Gaza last June, on Thursday telephoned Zahar to offer his condolences and to reiterate the PA's condemnation of the Israeli attack on the strip.

Abbas' spokesman Nabil Abu Rudeina called on Washington, Israel's main ally, to "intervene rapidly to prevent a further deterioration that may spin out of control, and to preserve the historical chance for peace," AFP news agency reported. He said the Israeli assaults "aim to deliver a blow to the Palestinian-Israeli negotiations."

Abu Rudeina's appeal, however, is seen as too little, too late, after U.S. President George W. Bush this week made Washington's position clear when he called for "rooting out terrorism in Gaza."

Bush made his remarks during his first official visit to Israel and the West Bank last week, during which he asserted his confidence of a Palestinian-Israeli peace deal and a Palestinian state before he leaves the White House in January 2009.

But Abu Rudeina's plea comes as no surprise following growing domestic criticism of Abbas' decision to pursue peace negotiations while Gaza was under fire from the Jewish state and with its ongoing expansion of settlements in the West Bank and East Jerusalem.

More than 125 Palestinians have been killed in Gaza since the Palestinians and Israelis formally re-launched their peace talks at the U.S.-sponsored Middle East conference in Annapolis, Maryland, where the largest number of Arab countries attended for the first time with Israel.

Hamas and other Palestinian factions blame Annapolis and Bush's call to eliminate "terrorism in Gaza" for providing an American and official Arab political cover for Israel to carry out its attacks.

Well-placed Palestinian sources told the Middle East Times that voices from within Fatah itself have joined Hamas in pressing Abbas to freeze the negotiations with Israel until the latter stops its crackdown and halts settlement activities.

The sources, which spoke on condition of anonymity, warned that if Abbas does not set conditions and boundaries for continuing the peace talks, Fatah risks facing a serious rift within its own ranks that not only threatens to torpedo the peace process and the establishment of a Palestinian state, but would also strengthen its rival Hamas.

While Arab commentators say the feuding Palestinian leaders could use Israel's military escalation on Gaza to unify their ranks and make peace with each other before making peace with their occupiers.