medical relief charity Medicins sans Frontieres (MSF) has hatted operations in part of west central African republic after a staff member was shot dead during an ambush on one of its convoys, it said on Thursday. The convoys carrying patients and doctors was stopped by unidentified armed men on Wednesday about 80 km north of Bossangoa, said a statement by the charity, known in English as Doctors Without Borders. Personal belongings and medicine were taken and one of the MSF drivers, a Central African republic national, was killed.