Both Prime Minister Ehud Olmert and Defense Minister Amir Peretz indicated Sunday that Friday's blast on a Gaza Strip beach that killed seven civilians may have been caused by the Palestinians, and not by the IDF. Peretz told the weekly cabinet meeting that he had established an investigative committee headed by a major-general, which is to present its findings on Tuesday. Peretz said the panel's preliminary findings showed that the Ghalia family was not killed by a shell fired by the IDF ground forces or the IAF. Peretz said that one of six artillery shells fired by the IDF was unaccounted for, but that there was a gap between when the shells were fired and the time the Palestinians said the shells landed. Peretz told the ministers that some 40 Kassam rockets were fired at Sderot and nearby communities over the weekend, and that Nati Angel - the Sderot man seriously wounded by a Kassam Sunday morning at a school near the city - was a "personal friend." Peretz lives in Sderot, where he used to be mayor. "We will work to protect our citizens, and the IDF is prepared to operate against all the [terrorist] organizations," he said. Peretz also told the cabinet that in the 24 hours ending Sunday Hamas had openly engaged in terrorism by firing rockets at Israel, and that starting a few days earlier the organization had become involved in the firing of rockets, both directly and indirectly. "I stress in the clearest way possible that we will act against all those engaged in terrorism, including Hamas, with all the means at our disposal," he said. Olmert opened the cabinet meeting by expressing Israel's "deep regret" over the incident, and saying that Peretz had set up an investigation. "Of course the exact details and the conclusions of the inquiry will be made public," he said. Olmert, who stressed that he was not apologizing because the facts were not yet clear, said past experience had shown that myths could be created that were divorced from the facts. He was referring to Muhammad al-Dura, the 12-year-old boy killed during an exchange of fire between the IDF and Palestinians on September 30, 2000. Images of Dura hiding behind his father and then being shot and killed were beamed across the world, with Israel widely blamed for his death until researchers three years later brought ballistic evidence showing that the shots could not have been fired by IDF soldiers. Regarding Friday's incident, Olmert said it must be made clear that Kassam rockets - designed to maim and kill Israelis - have been fired from the Gaza Strip continuously over the last few weeks. "This firing is very serious," he said. "It strikes at the fabric of life in communities in southern Israel and threatens peoples' lives... This is an unending series of terrorist attacks designed to strike at civilians." Olmert strenuously defended the IDF's actions. "I reject outright any and all attempts to impugn the army's morality. The IDF is the most moral military in the world; there has never been - and there isn't now - a policy of attacking civilians. I support the IDF commanders and soldiers who are working to halt the attacks on Israeli citizens in the southern part of the country." "At the same time," the prime minister said, "we will continue to act with full force against the firing of Kassam rockets, and will not refrain from operations that could thwart rocket firings, anywhere and in any situation, as necessary."