It was initiated after a decision by the Police Ombudsman, Dr Michael Maguire, to “call himself in” to investigate information he has been made aware of.

The Ombudsman is also investigating a number of complaints about a number of police officers’ alleged rogue social media accounts, including one which issued derogatory tweets about a solicitor.

Belfast-based human rights lawyer Kevin Winters, the subject of those tweets, said he would file a complaint with the Ombudsman.

Some of the other complaints have also alleged that officers used social media to leak confidential information about investigations.