FBI files reveal threat to kill Queen Elizabeth II during US visit in 1983

The FBI has revealed threats to kill the Queen in 1983 (Joe Giddens/PA)

An FBI file relating to a visit to the United States by the late Queen Elizabeth II has revealed a potential plot to assassinate her.

The document, available on the FBI’s online vault, outlines what appears to be intelligence provided to federal agents about a threat to the Queen’s life in California 40 years ago.