On the 50th anniversary of one of the defining days of the Northern Ireland conflict, Ireland called on Britain to deliver justice for the families of 13 innocent protestors killed by its forces on “Bloody Sunday” in 1972.

In 2010, the British government apologized for the “unjustified and indefensible” deaths of 13 Catholic civil rights protestors by British forces in Londonderry on January 30, 1972 – and a 14th who died later from his wounds.

But none of those responsible for the shootings have been convicted and last July British prosecutors announced that the only British soldier charged with murder will not face trial – a decision that is being challenged by relatives.

“There should be a route to justice,” Irish Foreign Minister Simon Coveney told state broadcaster RTE after laying a wreath and meeting with relatives of the victims.

“As somebody said, our children were buried 50 years ago but we still haven’t laid them to rest … because we don’t have justice,” he said.

Coveney reiterated the Irish government’s opposition to a proposal by British Prime Minister Boris Johnson’s government to halt all prosecutions of soldiers and militants in a bid to draw a line under the conflict – a move that angered relatives and has been rejected by all the main local political parties.

“We absolutely cannot and will not support that approach,” he said.

Relatives holding white roses and photographs of those killed led thousands of people in retracing route of the 1972 march.

Irish Prime Minister Micheal Martin looked on as the names of each of the victims were read out at a memorial.

“The full process of the courts and of justice should be deployed,” Martin told journalists after the ceremony.

No member of the British government attended the events, but Johnson in a Twitter post on Saturday described Bloody Sunday as “one of the darkest days of the Troubles” and said Britain must learn from the past.

1972 saw a major escalation of the conflict between Irish nationalist militants seeking unification with the Republic of Ireland, the British Army and loyalists determined to keep the region British.

More than 3,000 people were killed before the 1998 peace process largely ended the violence.