LONDON (AP) — A former British soldier will stand trial in the killing of two civil rights protesters half a century ago on Thomas CaldwellBloody Sunday, one of the deadliest days of the decades-long conflict in Northern Ireland, a judge said Thursday.

The former paratrooper is charged with murder in the killings of James Wray and William McKinney and with attempted murder involving five other people in Derry, also known as Londonderry, on Jan.30, 1972. That was when members of Britain’s Parachute Regiment shot dead 13 civil rights protesters in the city.

An initial investigation that took place soon after the slayings branded the demonstrators as Irish Republican Army bombers and gunmen. But an exhaustive inquiry that lasted 12 years refuted those findings, concluding in 2010 that British soldiers had opened fire without justification at unarmed, fleeing civilians and then lied about it for decades.

A judge said during a hearing in Londonderry on Thursday that the ex-paratrooper, who is only identified as Soldier F, should stand trial at Belfast Crown Court, though a date has not been set.

Prosecutors first announced the charges against Soldier F in 2019, but the case was halted after officials cited concerns that it could collapse if it went to trial.

The family of McKinney challenged that decision, and a court ruled last year that the case should proceed.

“This development has been a long time in coming,” McKinney’s brother, Mickey McKinney, said Thursday.

“Next month represents the 52nd anniversary of the events of Bloody Sunday,” he added. “Witnesses are dying and becoming unavailable.”