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An Israeli warplane bombed the Palestinian Foreign Ministry early Thursday, collapsing part of the structure and causing widespread damage in the area.

It was Israel's second use of a huge bomb in Gaza City in as many days in its two-week offensive to pressure Palestinian militants to release a captured Israeli soldier. At least 23 Palestinians were killed in Gaza on Wednesday.

The third and fourth floors of the Foreign Ministry were destroyed in the blast that shook the city and damaged houses and vehicles in the area. At least 13 people were injured, all in nearby houses.

The Israeli military confirmed it had carried out an airstrike on the ministry, noting that it is "led by Hamas." Israel's offensive is aimed primarily at Hamas, which claimed responsibility for the capture of the soldier in a cross-border raid on June 25.

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Israeli officials on Thursday accused Palestinian Foreign Minister Mahmoud Zahar of having known in advance of the militants' plot to attack an Israeli outpost and seize soldiers.

Zahar "is part of a leadership that is involved in a very tangible way in terrorism and in violence," said Israeli Foreign Ministry spokesman Mark Regev. "He had knowledge of the recent hostage taking, and he is part of a leadership that has orchestrated ... countless missile attacks against Israeli urban areas."

Foreign Ministry spokesman Taher al-Nunu accused Israel of carrying out "organized terrorism that targets all the Palestinian people and aims to exterminate all government institutions, one after another, to prevent them from carrying out their duties." He said no one was in the building when the plane struck after 1:30 a.m. Thursday.

In a separate attack, an Islamic Jihad militant was killed and another wounded in an Israeli airstrike before daybreak Thursday in southern Gaza, where Israeli troops started an incursion a day earlier. Palestinians said they were about to fire a rocket at a tank when they were hit. Four militants were wounded in an earlier airstrike there.

Early Wednesday, an Israeli F-16 warplane dropped a quarter-ton bomb on a house where militant leaders were meeting in Gaza City, killing nine people and wounding 37. A Hamas militant leader who has topped Israel's most-wanted list for a decade was badly wounded and underwent four hours of spinal surgery, security officials said.

The fugitive, Mohammed Deif, could end up paralyzed, Palestinian security officials said on condition of anonymity because they were not authorized to discuss his condition. Wednesday's blast marked the army's fourth attempt to kill Deif, held responsible for suicide bombings in Israel. In a 2002 missile strike, he lost an eye.

Israeli troops also killed at least 14 other Palestinians in four separate incidents on Wednesday, including Israeli tank fire and a gunfight in the central Gaza Strip.

More than 60 Palestinians have been killed thus far in the offensive, most of them gunmen, but about a dozen have been civilians. One Israeli soldier also has died, shot by fellow troops.

Israel has rejected demands that it release hundreds of prisoners in exchange for the soldier, Cpl. Gilad Shalit, 19.