Palestinians fired a Kassam from northern Gaza Thursday morning. No one was wounded and no damage was caused by the rocket which landed south of Ashkelon. The IDF was responding with artillery fire from outside the Strip. An IAF jet bombed the Hamas-controlled Palestinian Authority Foreign Ministry in Gaza City early Thursday, collapsing part of the structure and causing widespread damage. The third and fourth floors of the building were destroyed in the huge blast that shook the city and damaged houses and vehicles for a wide area around it. At least 13 people were injured, all in nearby houses. The IDF confirmed it carried out an airstrike on the Foreign Ministry, noting that it was "led by Hamas." A Hamas-allied group seized Cpl. Gilad Shalit last month, triggering the campaign. Israeli officials on Thursday accused PA Foreign Minister Mahmoud Zahar, a Hamas hardliner, of having known in advance of the 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 Foreign Ministry spokesman Mark Regev. "He had knowledge of the recent hostage taking, and he is part of a leadership that has orchestrated rocket attacks, countless rocket attacks...countless missile attacks against Israeli urban areas." PA 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. Before daybreak, an Islamic Jihad terrorist was killed and another wounded in an Israeli airstrike 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 other operatives were wounded in an earlier airstrike there. Overnight Tuesday, an IAF F-16 warplane dropped a quarter-ton bomb that killed nine members of one family in Gaza City. The Israelis were aiming for Hamas leaders, who were meeting in the house. A Hamas 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 Thursday. A high-ranking IDF source confirmed that Deif was in serious to critical condition. Deif could end up paralyzed, Palestinian security officials said. 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. Israel's air force targeted the two-story house of Nabil Abu Salmiyeh, a Hamas activist and university lecturer, after getting intelligence information that the leaders of Hamas's military wing, responsible for the abduction of the soldier, were meeting there. Palestinian security officials said seven or eight top Hamas officials were present. The bomb blast killed Abu Salmiyeh, his wife, and seven of his nine children, ages 4-18. "I heard a really loud explosion and then I felt the ceiling fall on top of me. I was buried under the rubble," said Awad Abu Salmiyeh, 19, who, along with an older brother, were the only family members to survive.