JERUSALEM (CNN) -- A U.N. team entered Gaza on Monday to investigate possible human rights abuses by Israel and Hamas during a three-week conflict that ended January 18.
Palestinians run from an Israeli airstrike on a U.N. school in northern Gaza on January 17.
Richard Goldstone, a former Rwanda and Yugoslavia war crimes prosecutor, is leading the Human Rights Council investigation of the conflict that claimed the lives of more than 1,000 Palestinians and 13 Israelis.
Goldstone and three other investigators entered Gaza via Egypt for a five-day visit.
Upon crossing into the Palestinian territory, Goldstone told reporters, "We've come here to see. We've come here to learn. We've come here to talk to people in all walks of life, ordinary people, governmental people, administrative people, obviously nongovernmental organizations that are so important in this sort of situation."
The Geneva, Switzerland-based Human Rights Council established the fact-finding mission April 3 "to investigate all violations of international human rights law and international humanitarian law that might have been committed at any time in the context of the military operations that were conducted in Gaza during the period from 27 December 2008 and 18 January 2009, whether before, during or after."
Israel launched its offensive in Gaza with the stated intent of stopping a barrage of rockets -- primarily short-range homemade Qassam rockets -- fired from the territory into southern Israel by Hamas fighters.
The Israeli government is not assisting the investigators, who are not scheduled to visit Israel as part of the inquiry.
Yigal Palmor, a spokesman for the Israeli Foreign Ministry, said that "there is not a chance we will cooperate with this mission" under the terms of the Human Rights Council mandate.
"The resolution was adopted by a vote of non-Democratic countries, and the democratic countries either abstained or rejected the resolution," Palmor said.
Israel has been long been a critic of the Human Rights Council, arguing that it is one-sided in its approach to the Jewish state.
The Israeli military conducted an investigation of its actions in the Gaza conflict and concluded in a report released in April that it "operated in accordance with international law." An Israeli human rights group called that conclusion problematic since an impartial external body did not lead the investigation.
The Palestinian Center for Human Rights has said that 1,417 Palestinians were killed in the fighting, of which 236 were active combatants. The Israeli military put the death toll at 1,166 and has maintained that more than half were "Hamas terror operatives"
The Hamas movement welcomed the arrival of the investigators. Fawzi Barhoum, a Hamas spokesman, said, "We are ready to help these committees and encourage them to unveil the truth and bring out all the hidden details of what took place during the war, hoping to show the entire world the truth."
Barhoum went on to say that Israel's lack of cooperation was evidence that it was trying to cover up crimes committed in Gaza.
The U.S. State Department has labeled Hamas, a Palestinian Islamic fundamentalist organization, a terrorist group. Its military wing, Izzedine al Qassam, has admitted responsibility for terrorist attacks against Israeli civilians as well as attacks against the Israeli military.