Mr Ihedioha was sacked as Imo state governor by the apex court last month.
Mr Diri is the successor of Henry Dickson whose tenure ended Friday night.
The declaration is in compliance with the directive of the Supreme Court.
The police boss added that the force would be part of the recruitment, training and deployment of personnel to be assigned for Amotekun operations.
Mr Lyon was sacked due to false documents submitted by his deputy Biobarakuma Degi-Eremienyo.
He said this is because aside from the APC, no other party met the requirement to man the position.
With the judgement, the APC has lost the state.
The new position of the governors was the outcome of a security meeting they had with the police boss in Enugu.
The State governor, Kayode Fayemi, who arrived at the scene, did on-spot assessment and refused to speak with newsmen.
The Ekiti State Commissioner for information and Civic Orientation, Muyiwa Olumilua, confirmed this in a statement.