The death of Oyibo Chukwu of the Labour Party happened three days before Saturday's general elections - which are being described as the country's most competitive polls in 24 years.

His aides who were with him were also shot dead before their car was set ablaze with the bodies inside, local outlets report.

“Our party members are being targeted for assassination by political parties that felt threatened by the rise of the Labour Party in the state and are afraid they may lose the Saturday’s election,” said Chijioke Edeoga, a candidate for the governor's seat in the state.

The Labour Party has not commented on the attack, but its presidential candidate Peter Obi has been urging supporters to vote "correctly, peacefully, and hopefully".