A man has been charged over a 1982 car bomb attack in central London which killed four soldiers.
The Irish Republican Army (IRA) claimed responsibility for the Hyde Park blast, which happened when members of the Royal Household Cavalry paraded towards Buckingham Palace.
A further 23 soldiers from the Household Cavalry, the Queen’s official bodyguard, which carries out ceremonial duties on state occasions, were wounded.
The soldiers had been due to carry out the Changing of the Guard.
John Downey, 61, from County Donegal in Ireland, is accused of four counts of murder and a charge under the explosives act.