A 37-year-old man arrested about a dissident republican murder attempt on a Catholic police officer in Derry has been released unconditionally.
The man was arrested in Ballymagroarty about the attack, linked to the New IRA group, on February 22.
A booby-trap bomb was placed under the policeman's home in Culmore in Derry.
He was later forced to move from the city.
Police are continuing to appeal for information.