He was arrested over allegations that he owns four properties and that he was allegedly transferring funds abroad through a third party.
He was arrested at the Wuse II office of the DSS on Monday afternoon and is now undergoing interrogation at the DSS Headquarters In Aso Drive.
The DSS in a 2016 report revealed that Magu was living in a N40m mansion.
“In December 2010, the Police Service Commission (PSC) found Magu guilty of action prejudicial to state security – withholding of EFCC files, sabotage, unauthorised removal of EFCC files and acts unbecoming of a police officer, and awarded him severe reprimand as punishment.