A man questioned by detectives from PSNI Legacy Investigation Branch in connection with a 1990 bomb attack that killed three police officers and a Catholic nun has been released.
The 55-year-old was arrested in Armagh on Thursday morning but later released by the PSNI pending a report to the Public Prosecution Service.
He was questioned on suspicion of a number of offences, including the explosion on the Killylea Road in Armagh on July 24, 1990, which claimed four lives.
Constable William Hanson, Reserve Constable Joshua Willis and Reserve Constable David Sterrit were all killed instantly when their unmarked patrol car ran over and detonated a 1,000lb landmine hidden in a culvert.
The blast lifted the car over a hedge into a field, where it landed on its roof.
A crater 30 feet wide and 20 feet deep was left behind.
Sister Catherine Dunne, who was in a car travelling in the opposite direction, was also caught in the explosion. She was the only nun killed as a result of the Troubles.
Another woman, a social worker, who had been travelling in the same car, was seriously injured.
According to the book Lost Lives, the IRA said at the time that the nun’s death had not been caused by “accidental or terrorist detonation of the device, but by a set of unforeseen and fluke circumstances”.
Sinn Fein’s Martin McGuinness offered an apology for her death.
A message from the pope was read out at her funeral, calling on all to recognise “the grievous injustice and futility of terrorism”.
Tarlac Connolly was later convicted of the murders and given a life sentence, but was released in 2000 under the terms of the Good Friday Agreement.
Welcoming the arrest, DUP MLA William Irwin said he hoped it would provide “renewed hope for the many families who have waited for years to see justice for their loved ones”.
He added: “I have vivid memories of this horrific attack by cowardly IRA terrorists on the Killylea Road in Armagh.
“This attack claimed the lives of four innocent people and wrecked a number of families who have had to live without closure now for over 27 years.
“I trust that this latest investigation moves swiftly and every effort is made to ensure that all those responsible for these heinous murders are brought to justice as soon as possible.”