Thirteen people were shot dead after members of the British Army’s Parachute Regiment opened fire on a civil rights demonstration in Londonderry.
At least 14 people were injured, one of whom later died.
Around 15,000 people gathered in Bogside, Derry to take part in a civil rights march on the morning of 30 January 1972.
The day became known as Bloody Sunday.
Here’s the background to Bloody Sunday, how the tragic day unfolded and what happened afterwards.
The Northern Ireland troubles escalated in 1969 when British troops were sent to suppress nationalist activity by the Irish Republican Army (IRA) and quell religious violence between Protestants and Catholics.
In August 1971, five months earlier, there was increasing violence and bombings in the north after a new law was introduced giving British authorities the power to imprison people without trial.
The government decided internment was the only way to restore order.
Thousands gathered in Derry on that January day to rally against internment, with the march organised by the Northern Ireland Civil Rights Association.
The Stormont government banned the protest and troops were deployed to police and patrol the march.
Bloody Sunday timeline
2.50pm - The march was due to start at 2pm but it was delayed 50 minutes by a stream of late arrivals. Protestors left Creggan Drive and set off for the city centre. Hundreds joined at every turn.
3.25pm - The march passed the Bogside Inn bar and continued on to William Street. Organisers claimed at this point up to 20,000 people were involved, while the Widgery Inquiry into the killings put it at 3,000 to 5,000.
3.45pm - The British Army erected barricades blocking the way to the Guildhall, the main body of the march. The protestors turned towards the revised rallying point at the Free Derry corner at the entrance to the nationalist Bogside estate. A number continued down William Street to confront soldiers at a barricade where some rioting ensued, including minor clashes between stone throwers. Security at this junction was common, with locals dubbing it ‘aggro corner’.
3.55pm - At a location away from the riot and march, soldiers in a derelict building on William Street fired a number of rounds after claiming they had come under attack. Two men were injured, one died six months later - John Johnston is acknowledged as the 14th victim of Bloody Sunday.
3.56pm - Rioters dispersed from William Street after the British Army deployed a water cannon.
4.07pm - Paratroopers, led by Major Ted Loden, are given an order to start arresting any remaining rioters in William Street. They are told not to engage in a running battle down Rossville Street.
4.10pm - The soldiers opened fire on people in the area of Rossville flats. Hugh Gilmour, Kevin McElhinney, Michael Kelly, John Young, William Nash and Michael McDaid were shot at a barricade beside the flats. James Wray, Gerald Donaghey, Gerald McKinney and William McKinney (not related) were shot at Glenfada Park on the other side of the street.
4.40pm - The shooting ends. Thirteen fatalities and at least 15 others wounded. The British Army claimed it came under fire in the Rossville flats area, allegedly by the Provisional IRA. But eyewitnesses insist none of the dead were armed.
What happened after Bloody Sunday?
The shootings led to widespread anger in Derry and across the country.
The day after Bloody Sunday the government announced there would be an inquiry led by the Lord Chief Justice, Lord Widgery.
The Widgery Tribunal largely cleared the soldiers and British authorities of blame, although Lord Widgery did describe the soldiers’ shooting as "bordering on the reckless".
The victims’ families regarded the inquiry as a whitewash and began their fight for justice.
The British Embassy in Dublin was burned to the ground by an angry crowd on 2 February 1972.
What did the Saville Inquiry find?
Prime Minister Tony Blair announced that a new inquiry would be held and in 1998 the Saville Inquiry was set up.
Headed by Lord Saville it became the longest-running inquiry in British legal history and cost about £200 million.
It reported back in 2010, concluding that none of the casualties were posing a threat or doing anything that would justify their shooting.
It said no warning was given to any civilians before the soldiers opened fire and that none of the soldiers fired in response to attacks by petrol bombers or stone throwers.
Lord Saville found there was "some firing by republican paramilitaries" but that on balance the Army fired first.
What happened after the Saville Inquiry?
The Police Service of Northern Ireland (PSNI) began a murder investigation after the Saville report was released.
Detectives submitted their files to the Public Prosecutions Service towards the end of 2016.
Prosecutors concluded on 14 March 2019 that soldier F will be prosecuted for the murders of James Wray and William McKinney and the attempted murders of Joseph Friel, Michael Quinn, Joe Mahon and Patrick O’Donnell in Londonderry in 1972.
On 2 July 2021, it was announced Soldier F would not face trial following a decision by the Public Prosecution Service (PPS).
In a statement, the PPS said after "careful consideration" the decision had been taken due to another recent court ruling which found that the evidence used for the prosecution of Soldier A and C for the killing of Joe McCann was inadmissible.
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