Former Secretary to the Government of the Federation, Babachir Lawal, has been detained by the Economic and Financial Crimes Commission (EFCC).
Recall that President Muhammadu Buhari had in October sacked Babachir Lawal over some allegations.
He was replaced by Boss Mohammed.
The EFCC Acting Head of Media and Publicity, Mr Samin Amaddin, confirmed his arrest on Wednesday.
Mr Amaddin said the former SGF is cooperating with investigators and has been making useful statements.