Africa News Tonight: Zuma aims to shake up South African election, Cameroon workers protest on May Day, Malawi urged to fight corruption

Former South African President Jacob Zuma has thrown his political weight behind a fresh rival to the ruling African National Congress, and adds more unpredictability to the elections. To mark Labor Day in Cameroon, hundreds of thousands of workers march against abuses they say include illegal dismissals and failure to pay the $70 monthly minimum wage. Economic and accountability bodies in Malawi urge the government to address flaws in the public procurement system, and counter corruption.