The violence began when a car bomb, planted by Ulster loyalists, exploded outside a crowded public house in the mainly Irish nationalist and Catholic district of Ballymurphy.

Most of the fighting took place along the interface between the Catholic Ballymurphy and Ulster Protestant Springmartin housing estates, and the British Army base that sat between them.

[3][4] At the time of the blast, the pub was crowded with men watching an association football match between England and West Germany on colour television.

The Secretary of State for Northern Ireland, William Whitelaw, told the House of Commons on 18 May that the blast was caused by a Provisional IRA bomb that exploded prematurely.

[3] A memorial plaque on the site of the former pub names three members of staff who lost their lives as a result of the bomb and the gun battles that followed.

"[7] The night before the bombing, gunmen from the UVF West Belfast Brigade had taken up position along the second floor of an abandoned row of maisonettes (or flats) at the edge of the Protestant Springmartin estate.

[3] Social Democratic and Labour Party Member of Parliament Gerry Fitt said that shots had been fired from the Springmartin estate only minutes after the bombing.

[8] Over the next few hours there were 35 separate shooting incidents reported, making it the most violent night since the suspension of the Northern Ireland government and imposition of Direct Rule from London earlier that year.

[3] According to journalist Malachi O'Doherty, a source claimed that the British Army had also fired into Belfast City Cemetery between the Whiterock and Springfield roads.

The first was 15-year-old Michael Magee, a member of Fianna Éireann (the IRA youth wing), who was found shot in the chest at New Barnsley Crescent, near his home.

[8] A death notice said that Magee was killed by the British Army but the republican publication Belfast Graves claimed he had been accidentally shot.

[8] On the first night of the battle, the Royal Ulster Constabulary (RUC) arrested two young UVF members, Trevor King and William Graham.

[12] When a British Army Major heard of the incident he ordered his men to withdraw, but they did not arrest the UVF members, who were allowed to hold their position.

His friend said that they had been walking home from a shop when there was a burst of gunfire, which "came from near the Taggart Memorial Army post and seemed to be directed towards Black Mountain Parade".

About three hours after the shooting of Pedlow, a bullet fatally struck a 13-year-old Catholic girl, Martha Campbell, as she walked along Springhill Avenue.