The presidential candidate of the Labour Party (LP), Peter Obi, has said that the killing of the United States humanitarian workers in Anambra State, South-East region of Nigeria by gunmen is one of the outcomes of a prolonged leadership failure and rising rate of unemployment and poverty in the country. It had been reported that gunmen ambushed a diplomatic convoy carrying US Embassy personnel on a humanitarian mission to Anambra on Tuesday and killed four people, including two police officers, at the Amiyi-Eke Ochuche axis in the Ogbaru council area of the state.