The United Nations on Thursday began an investigation into attacks on UN facilities during Israel's 22-day offensive in the Gaza Strip.

UN Secretary-General Ban Ki-moon said in a statement issued by his press office that the four-member Board of Inquiry, led by Ian Martin of Britain, began its work in New York on Thursday and was expected to travel to the region shortly.

The body will review and investigate several incidents in the Gaza Strip between December 27, 2008, and January 19, Ban said, and "in which death or injuries occurred at, and/or damage was done to, United Nations premises or in the course of United Nations operations."

The UN chief said that he expects that all parties will fully cooperate with the board, which also includes Larry Johnson of the United States, Sinha Basnayake of Sri Lanka and Lieutenant Colonel Patrick Eichenberger of Switzerland.

Upon completing its investigation the board will report to Ban, who will then review the findings and decide what steps to take, the statement said.

Following the Israeli attacks against UN institutions in Gaza, which came amid the offensive that Israel said was aimed at stopping rocket barrages by Palestinian militants, Ban conveyed "strong protest and outrage" to the Israeli government and demanded a "full explanation."