UNITED NATIONS, New York: Former UN secretary-general Boutros Boutros-Ghali, who led the world body during one of its most difficult periods, with failed missions in Rwanda and Bosnia, died Tuesday in Cairo. He was 93. The Egyptian diplomat became the first secretary-general from Africa in 1992, but his tenure ended abruptly five years later when the United States vetoed his second term. A former Egyptian foreign minister, the veteran diplomat headed the world body during one of its most difficult times with crises in Somalia, Rwanda, the Middle East and the former Yugoslavia. After a series of clashes with the US administration, Washington turned against Boutros-Ghali and decided to back Ghanaian Kofi Annan for the top post in late 1996.