At 10am on February 7th, 1991, the Provisional Irish Republican Army (IRA) launched a mortar attack on Downing Street in an attempt to assassinate the Prime Minister John Major and his War Cabinet.
This attack took place during The Troubles, a period of low-level war between the British authorities and Irish Republicans which spanned from the late 1960s until the Good Friday Agreement in 1998.
The attack began with a van, driven by an IRA member, being parked at the junction of Horse Guards Avenue and Whitehall, about 200 yards from Downing Street. The man left the van, exiting the scene on a motorcycle.
At 10:08am, three home-made mortar shells were launched from the van. Two shells landed near the Foreign and Commonwealth Office but one failed to detonate. The third shell exploded in the back garden of 10 Downing Street.
Had the shell struck 10 Downing Street itself, it is likely the entire cabinet would have been killed.*
At the same time as the mortars were launched, an incendiary device inside the van detonated so as to destroy any forensic evidence. There were no fatalities, although 4 people received minor injuries. The cabinet meeting was abandoned, to be reconvened in a different room less than ten minutes later.
The district was cordoned off by the police immediately after the attack as hundreds of officers were dispatched to prevent public access to anywhere from the Houses of Parliament to Trafalgar Square. The restrictions remained in place until 6pm that evening.