FOR over a century Irish republicans have been carrying out bomb attacks in Britain. As far back as 1867 the Fenians bombed Clerkenwell prison in London, killing several people in a jail break that went wrong.
During the War of Independence there were further incidents.
In January 1939 the IRA declared war on Britain once again and in that year an IRA explosion in Coventry killed a number of civilians.
There were no attacks during the 1956-1962 campaign, but early in the campaign from 1970 to 1994 the IRA carried out a series of bomb attacks in Britain. A few weeks after the Bloody Sunday killings in Derry on January 30th, 1972, a bomb exploded at Aldershot barracks where the Parachute Regiment was based. Seven people were killed and 15 injured.
The next major explosion was on the M62 when a bomb exploded on a coach carrying soldiers, killing 12 people, on February 4th, 1974.
On June 17th, 1974, the IRA bombed the 900-year-old Westminster Hall in London, and in July that year bombs exploded in Manchester, Birmingham and the Tower of London.
On October 5th, 1974, the Guildford bombings killed five people and further explosions occurred in the centre of London on October 11th, 22nd and 28th, causing no injuries.
The most serious bombing carried out by the IRA in Britain was in Birmingham on November 21st, 1974, when two bombs destroyed two pubs frequented by British army personnel. Twenty people died and 183 were injured.
The next high-profile bombing occurred in the car park of the House of Commons on March 3rd, 1979, when the INLA killed Airey Neave, the Tory shadow Northern Ireland secretary.
On October 10th, 1981, Chelsea Barracks was bombed by the IRA which used remote control detonation for the first time in Britain. Two people died and 40 people were injured.
A Week later, Maj Gen Stuart Pringle, Commander General of the Royal Marines, was seriously injured by a bomb attack in London.
On October 26th, 1981, a bomb in Oxford Street killed a police explosives expert who was trying to defuse it.
On November 13th, 1981, an IRA bomb exploded outside the home of the British Attorney General, Sir Michael Havers. On July 20th, 1982, the IRA struck again, killing eight soldiers with two bombs at Knightsbridge and Regent's Park in London.
On December 17th, 1983, a bomb exploded outside the Harrods store in London, killing six people, including three policemen. More than 90 people were injured.
Margaret Thatcher survived an attack on the Grand Hotel in Brighton on October 12th. 1984, where the Conservative Party was holding its annual conference. Five people died and 30 were injured.
While letter bombs and other minor explosions continued, the IRA struck again on September 22nd, 1989, with deadly effect. They killed 11 army bandsmen at the North Barracks at the Royal Marines School of Music in Deal, Kent.
The IRA again targeted another close associate of Ma g Thatcher, Ian Gow, and killed him with a car bomb outside his East Sussex home on July 30th 1990.
In the early 1990s, the IRA appeared to have taken a decision to increase the size of bombs they would plant in Britain, borne out by the Baltic Exchange bombing in the City of London on April 10th, 1992, which killed three people and injured 91, following the Conservative Party's victory in the general election.
In the run-up to the ceasefire, the IRA seems to have concentrated its attacks on London, striking at high-profile targets including Heathrow airport, into which they lobbed mortar bombs.
However, the IRA has long regarded London's docklands development, dominated by the Canary Wharf tower, Europe's tallest, as a top target in its bombing campaign in the UK.
A previous attempt, in November, 1992, was prevented by two security guards who spotted a van laden with a ton of explosives.
On that occasion, the detonator exploded but failed to set off the main charge. A second device was found nearby, but failed to go off.
But the bombers did not give up. In July 1994 just over a month before the ceasefire - an IRA lorry bomb with more than two tons of explosive was intercepted at Heysham ferry port in Lancashire.
Police believe it too, was destined for London, with the capital's docklands development the most likely target.