The IDF distributed leaflets addressing the Palestinian civilian population from the air, an IDF spokesperson announced Wednesday morning. The leaflets reiterated that the IDF's objective was to retrieve kidnapped soldier Cpl. Gilad Shalit, and warned the Palestinian public to stay clear of areas in which the IDF was operating. "The IDF is operating â€Žwith great caution in order to prevent any harm to uninvolved civilians. The operations targets terror organizations, the terror cells which launch projectile rockets at Israel and the terror infrastructure," the statement said. Earlier Wednesday morning, Muhammad Deif, an arch-terrorist who has been on Israel's most wanted list for a decade, was wounded in an IAF strike on a house in the Sheikh Radwan Gaza City in which at least nine members of the same family were killed, including seven children. However, Izzadin Kassam, Hamas's military wing, denied that Deif had been wounded. "It's completely untrue and we deny it completely. This is an attempt to deflect attention from the massacre of civilians by the Zionist enemy," a spokesman said. He refused to confirm that Deif had been in the building at the time of the attack. The strike occurred shortly after the army's entry into the central Gaza Strip for the first time since Operation Summer Rains commenced. The IAF struck a building in Gaza City that served as a meeting place for senior Hamas operatives to plan attacks against Israeli targets. Palestinian sources said that seven people were killed, including two children, and dozens more were wounded or trapped when the two-story house collapsed, trapping people inside. The house belonged to Hamas activist Dr. Nabil al-Salmiah. Deif was in the building at the time of the strike, but his condition was not immediately known. In addition, Ahmed Randur, one of those responsible for the abduction of Cpl. Gilad Shalit, was also wounded. Deif has survived at least two other targeted assassination attempts in the past. He is wanted for planning and implementing numerous terrorist attacks against Israeli citizens. Minutes later, witnesses said a car in the same neighborhood was targeted in an airstrike, wounding three people, witnesses said. Raed Saed, head of the military wing in Gaza City, was wounded and was being treated in a secret location. Earlier, Palestinians reported that a policeman was killed and another wounded by IDF troops in Deir el-Balah. Justice Minister Haim Ramon told Army Radio Wednesday morning that the IDF had been instructed to target those involved in terror. "We decided to target those we know are planning attacks and ordering Kassams fired on the western Negev," he said. Abu Obeideh, spokesman for the military wing of Hamas, issued an unusually strong condemnation, using language employed only when Israel has assassinated top Hamas leaders. "We will make the leaders of the Zionist regime regret this Nazi crime," said part of his long statement. Meanwhile, troops were operating in the towns of Khan Yunis and Deir el-Balah, where they had not entered since the beginning of the large-scale operation that followed the kidnapping of Shalit and the continuous barrage of Kassam rockets as far north as Ashkelon. The mission's objective was to stop Kassam rocket attacks on the western Negev. Columns of armored vehicles were poised to enter into Gaza earlier Tuesday. The incursion, officials said, would be an extension of Operation Summer Rains which began two weeks ago. IDF sources said that the operation would include naval, infantry and air forces working jointly to destroy the infrastructure supporting the launching of Kassam rockets. The green light for the operation was given Tuesday morning by Prime Minister Ehud Olmert and Defense Minister Amir Peretz. Earlier in the day, Olmert visited the IDF General Staff for the first time at the Kirya military headquarters in Tel Aviv and briefed the generals on the latest developments in the diplomatic efforts to retrieve Shalit. Before dawn Tuesday, IAF aircraft bombed a bridge in southern Gaza to impair the kidnapper's ability to move the abducted soldier. IDF sources said that close to 80 Palestinians have been killed since the beginning of the operation. Meanwhile Tuesday, the IDF shut down the Karni cargo crossing into the Gaza Strip after troops stationed inside felt tremors, believed to be coming from the digging of a tunnel underneath by Palestinian terrorists. Tanks and bulldozers began to try and locate the tunnel. Officials said they hoped the military operation would be completed by the end of the week and Karni would be reopened to allow the transfer of goods to the Palestinians. On Tuesday, Israel opened the Erez Crossing into Gaza to facilitate the transfer of goods to the Palestinians. "The situation of Gaza residents is difficult," said Maj.-Gen. Yosef Mishlav, coordinator of Government Activities in the Territories. "The situation is however far from turning into a humanitarian crisis." The UN, however, had claimed that Gaza was on the verge of a humanitarian crisis and on Saturday opened a shelter in a school in southern Gaza for 235 people who fled their homes because of the IDF operations. By Monday, the number being housed and fed in two schools had grown to 1,000, said John Ging, the new head of the UN Relief and Works Agency in Gaza, the agency that deals with Palestinian refugees. The UN also said that it had 230 containers of food waiting to pass through Karni cargo. If the containers didn't reach Gaza, Ging said, aid agencies would begin to run out of beans and whole milk this week. "This is just humanitarian relief, to keep the UN's emergency food distribution going," he said. "But commercial food shipments also are not getting through, and that's driving up the price of foods as basic as sugar, flour and powdered milk beyond what many Gazans can afford." Mishlav rejected the reports and said that truckloads of milk, medicine and flour were transferred on Tuesday into the Gaza Strip. In addition, he said the IDF had offered to open the Kerem Shalom crossing to enable some 500 Palestinians stuck in Egypt to return to their homes in Gaza. The offer, he said, was being considered by Palestinian Authority President Mahmoud Abbas. "Karni is being threatened," he said. "But we are doing everything we can to help the people by providing other solutions for the Palestinians." Israel has refused to open the main border crossing into Gaza at Rafah, fearing that Shalit would be smuggled out of Gaza and into Egypt.