The IRA has lost around 120 members as a result of premature explosions or accidental shooting incidents during the course of the troubles, although before Sunday night only three had been killed in England.
Accidental explosions, known in Belfast as "own goals", were a regular feature of the Seventies, with dozens of loyalists also being killed by their own devices.
One of the first IRA deaths came in 1970 when a bomb exploded as it was being made in a house in Londonderry. It killed three IRA men, one of whom was the householder, and two women living in the house. Another explosion in east Belfast in the early Seventies demolished several houses, killing four IRA men and four local people.
During the late Seventies the IRA in particular learnt to build safety features in to devices. These dramatically reduced the number of own- goal deaths so that in the Nineties they became rarities, rather than a regular feature of the IRA campaign.
They were never completely eradicated, however, as was demonstrated in the Shankill Road bombing of October 1993, when a bomb intended to kill loyalist extremists went off as it was being planted in a fish shop. The explosion killed an IRA member, Thomas Begley, together with nine Protestants.
In a handful of incidents during the Eighties IRA members died in explosions involving bombs, mortars, rockets, boobytraps and blast bombs.
The first IRA member to die in such an explosion in Britain was James McDade, killed in November 1974 while leaving a device at a Coventry telephone exchange. The local IRA responded to his death with what came known as the Birmingham pub bombings.
The other two deaths in Britain came in November 1991, when an inexperienced couple - Patricia Black, 18, and Frank Ryan, 26, who had been an IRA member for less than a year - died in St Albans, Hertfordshire, as they tried to blow up a military band.