FBI uncovers 1983 plot to assassinate Queen Elizabeth II during US visit.

Newly released F.B.I. documents reveal an assassination threat against Queen Elizabeth II before her visit to the United States in 1983, as well as other security concerns linked to the Irish Republican Army. The plot to kill the queen was shared with a San Francisco Police Department officer, who frequented an Irish pub called the Dovre Club, which the F.B.I. described as a gathering place for sympathizers of the Irish Republican Army. The documents also outline security concerns about some of the queen’s other visits to the United States.