A man who was arrested at Birmingham Airport by detectives investigating the murder of a police officer in an attack in Northern Ireland more than 30 years ago has been released unconditionally.

Constable Colleen McMurray, 34, was in a police car which was hit by a mortar bomb as it travelled along Merchants Quay in Newry on March 27 1992.

She suffered serious injuries and died in hospital, while another officer who had been driving the car suffered life-changing injuries.

No-one has ever been found responsible for the attack.

Following the release of the 59-year-old man who was arrested on Wednesday morning, the PSNI has said its investigation is continuing.