Before Cresswell’s arrest, several people, including relatives of Mrs Simpson, raised concerns about him.

He had a previous conviction for assaulting a woman in 2010.

The ombudsman’s investigation, which began in March 2021, resulted in a 1,400-page file being sent to the PSNI.

It found misconduct on the part of a number of officers, their cases being dealt with by the PSNI’s professional standards unit.

The inquest followed a series of complaints by Ms Simpson’s family over the police’s failure to treat her death as a murder at an earlier stage.

They are bringing a civil action against the PSNI.

It is understood that a number of further complaints about the case have been made to the ombudsman more recently.

They are now being investigated.