Chike Akunyili, the husband of the late boss of the National Agency for Food and Drug Administration and Control, NAFDAC, Dora Akunyili, was murdered by gunmen in Anambra on Tuesday.
Reports on Wednesday said he was shot dead while returning to Enugu from an event to honour his late wife.
His son, Obumneme Akunyili, confirmed the incident to BBC Igbo on Tuesday.
Some residents are alleging that the medical doctor was killed by gunmen suspected to be members of the separatist Indigenous People of Biafra (IPOB).
The militant group has vowed that the November 6 governorship election in Anambra State will not hold and has been blamed for a series of attacks on politicians and their supporters campaigning for the election.
The armed group, which has been accused of attacks on police stations and other security agencies in the region, is also using violent means to enforce a sit-at-home order, which it has decreed for every Monday in the five South-east states.
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