There are indications that a leader of the ruling All Progressives Congress (APC), Mr Jafaru Isa, may have returned part of the money he allegedly collected from the former National Security Adviser, Colonel Sambo Dasuki.
Mr Dasuki is facing trial over the alleged diversion of state funds of $2.1 billion meant for the purchase of weapons to tackle Boko Haram insurgency during the administration of Goodluck Jonathan.
Mr Isa was arrested last week in connection with the on-going investigation into the matter, in which prominent politicians in the country have been named to have received part of the money.
It was reported that the retired military officer, believed to be a close ally of the President, was released after he promised to return the remaining part of the money, claiming ignorance of the fact that the money was taken from government coffers.
Mr Isa is the first chieftain of the APC to be arrested by the EFCC since the beginning of a probe into the alleged diversion of $2.1 billion meant for arms purchase by officials of the immediate-past administration.