A United Nations probe of last year's conflict in Gaza concluded Tuesday that both sides were guilty of committing war crimes, including the violation of human rights and international humanitarian law. In a 575-page report, the fact-finding mission, headed by former South African Judge Richard Goldstone, found that "Israel committed actions amounting to war crimes, possibly crimes against humanity," during last year's Operation Cast Lead, which targeted Palestinian rocket squads in Gaza. Based on numerous public hearings and testimony from experts and victims in Gaza and Geneva, the report also found that "Palestinian armed groups committed war crimes," including firing rockets into civilian areas in southern Israel. "There should be no impunity for international crimes that are committed," Goldstone told reporters at a news conference in New York. "It's very important that justice should be done." Appointed by the Human Rights Council in April, the mission was charged with investigating 36 specific incidents in Gaza and others in the West Bank and Israel. In all, the mission conducted 188 interviews, reviewed 10,000 documents and viewed 12,000 photos and videos. Among its main findings, the mission said Israel imposed a blockade around Gaza that amounted to "collective punishment," and further carried out a "systematic policy of progressive isolation and deprivation of the Gaza Strip." More than 1,400 people were killed during the military operation, and houses, factories, wells, schools, hospitals, police stations and public buildings were destroyed. The report portrayed a military operation that used disproportionate force aimed at civilians, amounting to "direct attacks against civilians with lethal outcomes," including the targeting of a mosque during prayer time that killed 15 people. A "direct and intentional" attack on Al Qud's hospital as well as shelling in Gaza City's Zeitoun neighborhood - where shells hit a house in which civilians were forced to congregate - constituted a war crime, the report found. "Taking into account the ability to plan, the means to execute plans with the most developed technology available and statements by the Israeli military that almost no errors occurred, the Mission finds that the incidents and patterns of events considered in the report are the result of deliberate planning and policy decisions," investigators wrote. On the Palestinian side, the report concluded that repeated rocket and mortar attacks into southern Israel by Palestinians constituted "war crimes and may amount to crimes against humanity" because they did not distinguish between military and civilian targets. "Where there is no intended military target and the rockets and mortars are launched into civilian areas, they constitute a deliberate attack against the civilian population," the report found. Among its recommendations, investigators said the Security Council should require Israel to launch an investigation into the conflict within three months. An independent body should be set up to monitor the progress of such an investigation and subsequent prosecutions, and if no progress is made within six months, the Council should refer the situation to International Criminal Court prosecutors. A similar effort should be undertaken on the Palestinian side, with the independent body reporting to the Security Council on progress there. "We've received a copy of Judge Goldstone's report regarding the alleged human rights allegations during the Gaza conflict," a US official told The Jerusalem Post on Tuesday. "As the report is lengthy, and the issues it address are complex, the findings will take time to digest and we are reviewing it carefully." United States Ambassador Susan Rice was appointed president of the Security Council during the month of September. Goldstone, who is Jewish, said he has strong ties to Israel and noted his attempt to maintain objectivity during the probe. "Speaking from that point of view, it's obviously a great disappointment to me, putting it mildly, that Israelis have behaved in the way described in the report," he told reporters. Earlier this year, the Israeli army denied wrongdoing during the war. Since then it has opened a serious of separate investigations, which Goldstone said were insufficient. "The Israeli investigations have been conducted secretly by the military," which "relied only on the evidence given to them by their own soldiers," he said, comparing that strategy to a "domestic police force in Manhattan investigating murders by only speaking to murderers."