The former governor of Edo State, Lucky Igbinedion, underwent hours of questioning by operatives of the Economic and Financial Crimes Commission (EFCC) on Thursday.
A source said the grilling interview was in respect of a criminal diversion of public funds to the tune of N1.6 billion.
The former governor, who arrived at the headquarters of the EFCC, at Jabi, Abuja, around 2:00 p.m., on Thursday was still being quizzed as of midnight.
Shortly after his exit as governor in 2007, Mr Igbinedion was prosecuted by the EFCC and convicted for corruption.
But the new investigation, according to the source who was not authorised to speak on the matter, was based on fresh evidence against him.
The source said that the former governor diverted a loan obtained by the Edo State Government to finance an investment during his tenure, to settle the financially indebtedness of a company in which he had interest.
Wilson Uwujaren, EFCC spokesperson, confirmed the invitation of the former governor but declined further comment.