Operation Flavius was a military operation in which three members of a Provisional Irish Republican Army (IRA) cell were shot dead by undercover members of the British Special Air Service (SAS) in Gibraltar on 6 March 1988. The three Sen Savage, Daniel McCann, and Mairad Farrell who were members of Provisional IRA Belfast Brigade were believed to be mounting a car bomb attack on British military personnel in Gibraltar. Plain-clothed SAS soldiers approached them in the forecourt of a petrol station, then opened fire, killing them. All three were found to be unarmed, and no bomb was discovered in Savage's car, leading to accusations that the British government had conspired to murder them. An inquest in Gibraltar ruled that the SAS had acted lawfully, while the European Court of Human Rights held that, although there had been no conspiracy, the planning and control of the operation was so flawed as to make the use of lethal force almost inevitable. The deaths were the first in a chain of violent events in a fourteen-day period. On 16 March, the funeral of the three IRA members was attacked by a loyalist wielding pistols and grenades, leaving three mourners dead. Then, at the funeral of one of the mourners, the IRA shot two plain clothed British soldiers who had driven into the procession in error.

From late 1987, the British authorities were aware that the IRA was planning to detonate a bomb at the changing of the guard ceremony outside the governor's residence in the British Dependent Territory of Gibraltar. When Savage, McCann and Farrell travelled to Spain in preparation for the attack, they were tracked at the request of the British government. On the day of the shootings, Savage was seen parking a white Renault in the car park used as the assembly area for the parade; McCann and Farrell were seen crossing the border shortly afterwards.

After a military bomb disposal officer reported that Savage's car should be treated as a suspected bomb, the police handed over control of the operation to the SAS. As soldiers were moving into position to intercept the trio, Savage split from McCann and Farrell and began running south. Two soldiers pursued Savage while two approached McCann and Farrell; as they did so, the pair were said to make threatening movements, as a result of which the soldiers opened fire, shooting them multiple times. As soldiers caught up with Savage, he was alleged to have turned around to face them while reaching into his jacket; he was also shot multiple times. All three were subsequently found to be unarmed, and Savage's car was found to contain no explosives; enquiries resulting from keys found on Farrell led authorities to a second car, containing a large quantity of explosives, in a car park in Spain. Almost two months after the shootings, the documentary "Death on the Rock" was broadcast on British television. Using reconstructions and eyewitness accounts, it presented the possibility that the three IRA members had been unlawfully killed. The documentary proved extremely controversial; several British newspapers described it as "trial by television".The inquest into the deaths began in September 1988. It heard from British and Gibraltar authorities that the IRA team had been tracked to Mlaga Airport, where they were lost by the Spanish police, and that the three did not re-emerge until Savage was sighted parking his car in Gibraltar. The soldiers each testified that they had opened fire in the belief that the suspected bombers were reaching for weapons or a remote detonator. Among the civilians who gave evidence were the eyewitnesses discovered by "Death on the Rock", who gave accounts of seeing the three shot without warning, with their hands up, or while they were on the ground. Kenneth Asquez, who told the documentary that he had seen a soldier fire at Savage repeatedly while the latter was on the ground, retracted his statement at the inquest, claiming that he had been pressured into giving it. On 30 September, the inquest jury returned a verdict of "lawful killing". Dissatisfied, the families took the case to the European Court of Human Rights. Delivering its judgement in 1995, the court found that the operation had been in violation of Article 2 of the European Convention on Human Rights as the authorities' failure to arrest the suspects at the border, combined with the information given to the soldiers, rendered the use of lethal force almost inevitable. The decision is cited as a landmark case in the use of force by the state.

The Irish Republican Army (IRA; Irish: Óglaigh na hÉireann), also known as the Provisional Irish Republican Army, and informally as the Provos, was an Irish republican paramilitary organisation that sought to end British rule in Northern Ireland, facilitate Irish reunification and bring about an independent, socialist republic encompassing all of Ireland. It was the most active republican paramilitary group during the Troubles. It saw itself as the army of the all-island Irish Republic and as the sole legitimate successor to the original IRA from the Irish War of Independence. It was designated a terrorist organisation in the United Kingdom and an illegal organisation in the Republic of Ireland, both of whose authority it rejected.

The Provisional IRA emerged in December 1969, due to a split within the previous incarnation of the IRA and the broader Irish republican movement. It was initially the minority faction in the split compared to the Official IRA, but became the dominant faction by 1972. The Troubles had begun shortly before when a largely Catholic, nonviolent civil rights campaign was met with violence from both Ulster loyalists and the Royal Ulster Constabulary (RUC), culminating in the August 1969 riots and deployment of British soldiers. The IRA initially focused on defence of Catholic areas, but it began an offensive campaign in 1970 that was aided by weapons supplied by Irish American sympathisers and Libyan leader Muammar Gaddafi. It used guerrilla tactics against the British Army and RUC in both rural and urban areas, and carried out a bombing campaign in Northern Ireland and England against military, political, and economic targets, and British military targets in Europe.

The Provisional IRA declared a final ceasefire in July 1997, after which its political wing Sinn Féin was admitted into multi-party peace talks on the future of Northern Ireland. These resulted in the 1998 Good Friday Agreement, and in 2005 the IRA formally ended its armed campaign and decommissioned its weapons under the supervision of the Independent International Commission on Decommissioning. Several splinter groups have been formed as a result of splits within the IRA, including the Continuity IRA and the Real IRA, both of which are still active in the dissident Irish republican campaign. The IRA's armed campaign, primarily in Northern Ireland but also in England and mainland Europe, killed over 1,700 people, including roughly 1,000 members of the British security forces, and 500–644 civilians. In addition 275–300 members of the IRA were killed during the conflict.