The Irish Republican Army has long sought to unite the independent country of Ireland with Northern Ireland, which is part of the United Kingdom. A split developed within the IRA around 1970 over tactics, and the Provisional IRA -- which has carried out many bombings and assassinations, including the murder of Lord Mountbatten -- emerged as the dominant group. Despite recent peace talks and cease-fire agreements, IRA dissidents have continued to use violence to achieve their ends. An excerpt from The Post of Aug. 28, 1979:

By Leonard Downie Jr.

Washington Post Staff Writer Foreign Service

LONDON, Aug. 27 --

Lord Louis Mountbatten, the elder statesman of Britain's royal family, was assassinated near his vacation home in Ireland and at least 18 British soldiers were killed across the border in Northern Ireland in apparently coordinated bombing attacks by Irish Republican Army terrorists.

With at least 22 people dead altogether, it was the worst single day of killing since British troops were sent to Northern Ireland 10 years ago this month to quell sectarian violence there. ...

Buckingham Palace officials said Queen Elizabeth was "deeply shocked" by the death of Mountbatten, her second cousin.

Lord Mountbatten, 79, a celebrated World War II naval commander and later the last viceroy of India, was killed by a massive explosion that blew apart his 29-foot yacht, Shadow V, just after noon today. The ship was leaving the picturesque resort harbor of Mullaghmore on Ireland's northwest coast, about 15 miles from the Northern Ireland border. Mountbatten's 14-year-old grandson, Nicholas Knatchbull, and 16-year-old Paul Maxwell, who was crewing the craft, were also killed by the blast.

Mountbatten's daughter, Lady Patricia Brabourne, her husband, film and television producer Lord Brabourne (John Ulick Knatchbull), his mother, the Dowager Lady Brabourne and his son, Timothy, who was Nicholas' twin brother, all were critically injured in the explosion. They are in the intensive care unit of a hospital in nearby Sligo, Ireland.

The outlawed Provisional IRA issued a statement claiming responsibility for "the execution today of Lord Louis Mountbatten" and describing the bomb that blew up his yacht as 50 pounds of explosives detonated by remote control.

At the same time that statement was being made to news organizations in Ireland and Britain -- five hours after Mountbatten was slain -- two more massive explosions killed at least 18 British soldiers and one civilian and seriously injured at least eight other soldiers near the village of Warrenpoint in County Down, just across the border in British-ruled Ulster on the eastern coast of Northern Ireland.

The well-planned ambush used two big bombs, one in a truck loaded with hay and another minutes later in a nearby stone house. The first bomb caught a passing truckload of troops and the second hit the reinforcements sent in to rescue them.

There were also reports that the soldiers were fired on by gunmen with automatic rifles between the two blasts and that local residents, golfers from a nearby course and passing tourists were injured by the explosions and gunfire.

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