JERUSALEM — In the deadliest attack of its intensifying war in the Gaza Strip, the Israeli military struck a United Nations-run school Tuesday where hundreds of Palestinians had sought refuge from the fighting. As many as 40 people were killed, many of them children, and 55 were wounded, U.N. officials said.
Israel moved quickly to explain the attack, saying that its forces had been fired on first. Military officials said fighters from the militant Islamic group Hamas had lobbed mortar rounds at Israeli forces from the school, in the Jabaliya refugee camp in northern Gaza, and Israeli forces returned fire outside the school moments later.
Two members of a Hamas mortar crew were among the dead, Israeli officials said.
However, John Ging, the top U.N. refugee official in Gaza, said U.N. staff and Palestinian families in the school compound had been screened for weapons, and he disputed Israel's claim that mortars were fired from inside.
"As far as we are concerned that is not true, but if Israel has evidence of that they need to provide it to an independent inquiry," Ging said.
It was impossible to reconcile the conflicting accounts because Israel has prevented reporters from entering Gaza since its 11-day-old offensive against Hamas started, despite a court order directing the military to do so. The few television images from Jabaliya showed chaos and confusion, with some Palestinians wailing in grief and one apparently injured child, wearing striped socks, being rushed from the scene. It was impossible to get firsthand accounts.
Israeli officials blamed Hamas, saying that militants have used civilians as shields and infiltrated U.N. schools in the past, an assertion that U.N. officials didn't dispute. Although Israel said its return fire landed outside the school, witnesses described a series of explosions, which Israeli officials said suggested that militants had rigged the building with explosives.
"We face a very delicate situation where the Hamas is using the citizens of Gaza as a protective vest," military spokesman Brig. Gen. Avi Benayahu said.
The Jabaliya strike pushed the Palestinian death toll in the war to more than 600, with nearly 3,000 wounded, U.N. officials said.
Less than 24 hours earlier, three men were killed in an Israeli strike on a U.N. school in Gaza City where more than 400 Palestinians had gone to seek shelter.
The incidents renewed questions about Israel's ability to wage a precision war in densely populated Gaza even as its forces pushed deeper into the narrow territory.
Israel said it had killed 130 Hamas militants since the start of the campaign, and on Tuesday it attacked the Jabaliya home of Iman Siam, a senior operative and head of the group's rocket-launching unit. A military official said Siam was thought to be home at the time, although it wasn't clear whether he had been hit.
Israeli news media reported that ground forces were edging closer to the southern Gaza town of Khan Younis and continued to surround Gaza City, where they were coming under some of the toughest resistance they'd faced, including militants equipped with anti-tank rockets. Four Israeli soldiers were killed in two separate "friendly fire" incidents Monday, bringing to six the number of Israeli military fatalities in the conflict.
The onslaught hasn't stopped militants in Gaza from firing rockets into Israel, which Israeli leaders have cast as the main reason for the invasion.
Israeli police said that 35 more rockets landed in Israel on Tuesday, including in the town of Gedera, about 25 miles from the Gaza border and 20 miles from the Israeli city of Tel Aviv. It was the northernmost point that a rocket had landed since the war began, and Israeli media reported that a 3-month-old infant was lightly wounded.
On the Gaza side of the border, humanitarian groups are warning of a worsening situation, with ambulances unable to reach sick and wounded people due to the ongoing fighting.