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GAZA - Israel launched air strikes in Gaza today against a Hamas security force, killing at least four people and plunging Palestinians deeper into turmoil after six days of fierce internal fighting verging on civil war.
Israeli troops with tanks also entered the Gaza Strip, the coastal enclave from which Israel withdrew in 2005. A spokesman called it a "small force" on a "defensive operation", leaving it unclear whether Israel was shifting its policy of leaving all but the areas closest to the border to Palestinian forces.
Rubble was all that remained of a downtown Gaza City building that housed Hamas' Executive Force, which Palestinian President Mahmoud Abbas' Fatah faction wants disbanded. At least 40 people were wounded in that attack alone, hospital officials said.
Israeli artillery batteries were deployed along the Gaza border and local residents said tanks were moving towards northern Gaza towns. The army had no comment on the movements. Israeli forces recently completed training for a possible ground invasion of Gaza.
The Israeli army broke into local radio broadcasts to warn northern Gaza residents not to approach Israeli forces operating in the area.
Despite a ceasefire deal brokered by Abbas and Hamas leader-in-exile Khaled Meshaal, four Palestinians -- including a woman and a young boy -- were killed in fighting between Hamas and Fatah today, raising the death toll in such internal conflict to at least 44 since Friday.
Israel said it launched the air strikes in response to cross-border rocket attacks. Hamas accused Israel of colluding with its rival Palestinian faction Fatah in a battle for dominance in the territory, which Israeli soldiers and settlers quit two years ago.
Fatah brushed aside Hamas' charges, saying Palestinians must unite in the face of the Israeli onslaught.
"We have had enough. Israel will take all defensive measures to protect our citizens from these Hamas rockets," Miri Eisin, a spokeswoman for Israeli Prime Minister Ehud Olmert, said before the air strikes.
In response to the intense air assault, Hamas' armed wing threatened to resume suicide bombings in Israel. A Hamas bomber last struck in Israel in 2004.
After the Executive Force building was hit, an Israeli aircraft destroyed a car carrying a senior commander in Hamas' armed wing, seriously wounding him and killing another militant.
Another Hamas fighter was killed in an air strike at an Executive Force position outside the home of the Interior Ministry's spokesman.
In southern Gaza, an Israeli air strike targeting a rocket launching crew killed two teenage brothers whom hospital officials described as civilians.
The Israeli army denied its attacks were connected to the factional violence. The air strikes came after militants in Gaza fired rockets at the southern Israeli town of Sderot and injured two people. Rockets have continued to fall throughout the day on southern Israel despite the air strikes.
The Gaza violence has worsened conditions for Palestinians hard-hit by Western sanctions against the Hamas-led government. Olmert has ruled out serious peace talks so long as the government refuses to recognise Israel and renounce violence.
Abbas called off plans to travel to Gaza today for crisis talks with Prime Minister Ismail Haniyeh of Hamas. It was unclear how the Hamas-Fatah unity government would survive and function given the mounting violence and resentment.
Israel's air strikes came a day after it hit an Executive Force building in southern Gaza and a rocket launching crew, killing five people. The Israeli government has threatened a "severe" response to rocket attacks on Israel.
Olmert, struggling to stay in office after an official report sharply criticised his handling of last year's war in Lebanon, is under heavy domestic pressure to stop the rockets without getting bogged down in another inconclusive conflict.
At the same time, he knows a wide-ranging Israeli military response in Gaza could have a major influence on the course of Fatah's power struggle with Hamas.
The United States said Israel had the right to defend itself against Hamas rocket fire and praised the Jewish state for "great restraint" in recent days.
- REUTERS