The head of the Police Service of Northern Ireland (PSNI) and other senior officers are facing an investigation over claims of alleged misconduct in public office.
The allegations relate to how the force handled an inquiry in 2014 into the awarding of vehicle contracts.
The PSNI says Chief Constable George Hamilton and other senior officers have been informed of the complaints made against them by former senior officers.
The Northern Irish Police Ombudsman Dr Michael Maguire is investigating the matter.
In a statement, the PSNI said: "The Chief Constable, Deputy Chief Constable and other officers completely refute the allegations made against them and are strongly of the view that these complex investigations into the complainants were conducted with professionalism and integrity.
"We have full confidence in the [Ombudsman's office] to complete a thorough investigation and we trust that they are left to do so without ongoing public commentary."