The United Nations Truce Supervision Organization in Palestine (UNTSO), an observer mission, was set up under a Security Council resolution in May 1948 to assist the Mediator and the Truce Commission in the supervision of the truce in Palestine. Its activities, which have evolved along with the various changes of the Middle East problem, are spread over the territory of five States. The main tasks of UNTSO at present are to observe and report on breaches of the cease-fire and to help prevent incidents. It also reports to the Secretary-General on complaints submitted by the parties concerned and the enquiries conducted by U.N. military observers at the request of the parties. A view of UNTSO Liaison Office in Cairo, Egypt.