The Provisional IRA had first attacked Great Britain in March 1973 with car bombs in London which injured over 200 people . Beginning in October 1974 the IRA launched a sustained bombing campaign in England which lasted until December 1975 when the IRA unit responsible for the campaign was caught after a 6-day siege . Thereafter the IRA launched more sporadic but more spectacular attacks on Britain which generated worldwide publicity like the Hyde Park and Regent 's Park bombings ( which killed 11 British soldiers , injured dozens of soldiers and civilians and killed 7 horses ) and an attempt to kill the then British Prime Minister Margaret Thatcher with the 1984 Brighton bombing . In September 1989 , the IRA launched what became another more sustained bombing campaign on Britain when they bombed Deal barracks , killing 11 bandsmen . In May 1990 a British Army Service Education Centre in Eltham , S London SE9 , injuring five people . On 7 February 1991 the IRA carried out mortar attack Downing Street an attempt to assassinate Prime Minister John Major and his War Cabinet , who were meeting to discuss the Gulf War . One of the heavy mortar shells exploded in the back garden of number 10 , only yards from the cabinet office . Due to the bomb-proof windows , none of the cabinet were hurt , though four other people received minor injuries , including two police officers . The other two shells overshot Downing Street and landed on a green nearby . In 1992 the IRA launched over 30 attacks on Britain . Unlike the campaign in the 1970s , the 1990s bombing campaign in England was aimed more at economic targets . In April 1992 the IRA exploded two bombs at the Baltic Exchange in the centre of London and killed three people , including a 15-year-old girl . The IRA warning proved to be inadequate and added to the confusion as it mentioned the Stock Exchange , there it was reported in the media that insurance claims amounted to £ 800 million . The estimated figure for the whole of Northern Ireland since the start of the conflict back in 1969 until then was £ 615 million . Almost a year later the 1993 Bishopsgate bombing killed one man and injured over 30 people in the explosion . Later estimates put the cost of repair for the Bishopsgate bomb at £ 350 million ( some initial reported estimates were as high as £ 1 billion )
Downing Street
Downing Street mortar attack
Heathrow mortar attacks