British police announced on Tuesday that they had arrested an ex-soldier who is believed to be linked to the Bloody Sunday killings in Londonderry, Northern Ireland, in 1972, which helped spark three decades of violence known as The Troubles.

"Detectives from Legacy Investigation Branch investigating the events of Bloody Sunday have arrested a 66-year-old man in County Antrim," the Police Service of Northern Ireland said in a statement, according to AFP.

"The suspect is being interviewed at a police station in Belfast," the statement continued, adding that the arrest marked "a new phase in the overall investigation which would continue for some time."

This marks the first arrest since a murder investigation was opened in 2012 into the killings of 13 civil rights protesters in the streets of Londonderry, which both hardened anti-British sentiment in Northern Ireland and led to many fresh recruits for the Irish Republican Army, according to CNN.

The defense ministry said it was only "aware an ex-soldier has been arrested," saying that it has no other knowledge of the proceedings in the investigation.

"It would be inappropriate to comment further on an ongoing criminal investigation at this stage," the ministry said in a statement, according to the BBC.

In 2010, Prime Minister David Cameron apologized to the Bloody Sunday victims on behalf of the state, following the results of a 12-year inquiry which unequivocally blamed the army for the civilian deaths. It exonerated those who died, and concluded that soldiers fired the first shot and gave no warning before opening fire.

Accepting the findings of the inquiry, Cameron said he was "deeply sorry" while describing the killings as "unjustified and unjustifiable."