Airstrike kills 3 at Gaza school U.N. using as refugee center

JERUSALEM — An Israeli military strike killed three people at a United Nations-run elementary school in Gaza City where more than 400 Palestinians had sought shelter from the intensifying ground war in the Gaza Strip, U.N. officials said Tuesday.

The officials said the strike late Monday was a direct hit on a compound clearly marked as a U.N. installation. The U.N. said it was strongly protesting the incident and called on Israel to investigate it immediately. The Israeli army had no immediate comment.

The three civilian deaths added to the mounting toll in Israel's 11-day-old offensive in Gaza against the militant Islamic group Hamas.

Gaza health officials said that 562 Palestinians had been killed _ including at least 111 children _ and some 2,500 wounded. The figures can't be independently verified because Israel has barred foreign journalists from Gaza since the offensive started.

Three Israeli soldiers died in a "friendly fire" incident Monday night when an Israeli tank mistakenly fired on an infantry unit that was taking up positions in a northern Gaza Strip building.

Israeli military officials said that a fourth soldier was killed in a separate friendly-fire incident Monday in northern Gaza. Initial reports indicated that a tank shell fired by mistake struck the soldiers.

Up to Monday, one Israeli soldier had been killed in the military campaign. Some Israelis say that the operation is entering a crucial phase in which expanding ground operations could lead to greater Israeli military casualties.

Israeli officials said they'd killed 130 militants over the past two days in military operations that they say are aimed at destabilizing Hamas and stopping its fighters from firing crude rockets from Gaza into Israeli territory.

On Tuesday, Israel said it had attacked the home of Iman Siam, a senior Hamas military operative and the head of the group's rocket-launching unit, in the northern Gaza neighborhood of Jabaliya, although it didn't immediately say whether Siam had been killed.

Humanitarian officials have warned of a rapidly worsening crisis in Gaza, where most residents are without power and running water and hospitals are struggling to cope with wave on wave of injuries. Thousands of people have been forced to flee homes that have been damaged by the fighting, U.N. officials say.

The Israeli strike on the Asma Elementary School killed three members of a family _ men aged 19 to 25, the U.N. said. They were among more than 400 residents of the northern Beit Lahiya neighborhood who'd fled the fighting near their homes earlier Monday night.

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