These attacks were the first in a year-long campaign by an IRA Active Service Unit who became known as the Balcombe Street Gang – who Police arrested in December 1975 after the Balcombe Street siege leading to their trial and conviction for other murders and offences . A similar bomb to those used in Guildford , with the addition of shrapnel , was thrown into the Kings Arms pub in Woolwich on 7 November 1974 . Gunner Richard Dunne and Alan Horsley , a sales clerk , died in that explosion . On August 27 , 1975 the same IRA unit detonated a bomb in Surrey at the Caterham Arms pub which injured over 30 people , Surrey police said it was " a carbon copy of the Guildford bombs " . The bombings contributed to the speedy and unchallenged passing of the Prevention of Terrorism Acts in November 1974 , which were then misused by the Metropolitan Police to force false confessions from the " Guildford Four "
Caterham Arms pub which injured over 30 people
Caterham Arms pub bombing
Guildford pub bombings