Israeli air strikes hit Hamas in Gaza, troops enter

By Nidal al-Mughrabi

GAZA (Reuters) - Israel launched air strikes in Gaza on Thursday 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.

Israeli Prime Minister Ehud Olmert vowed to stand firm on a visit to a border town hit by dozens of rockets in recent days and U.S. President George W. Bush, calling for both sides to seek peace, said he understood Israeli fears of rocket strikes.

Rubble was all that remained of a Gaza City building that housed the Islamist Hamas's Executive Force, which Palestinian President Mahmoud Abbas's secular Fatah faction wants disbanded. At least 40 people were wounded in that attack alone, hospital officials said.

Israeli artillery was deployed along the Gaza border and residents said tanks were moving towards northern Gaza towns. 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 on Thursday, 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 Fatah in a battle for dominance in the territory, which Israeli soldiers and settlers quit two years ago.

Fatah brushed aside Hamas's 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 Olmert, said before the air strikes.

In response to the intense air assault, Hamas's 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's 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 said were civilians. Three Hamas fighters were killed and seven wounded in an overnight strike on a training base.

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.

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