In 1983, there was a plot to kill Queen Elizabeth. During her visit to the US, authorities learned of an Irish Republican Army sympathizer wished to kill her during her tour of California. The FBI recently declassified these documents, per People.

The Queen and Prince Philip were invited by former President Ronald Reagan to see his home state forty years ago. Weeks before their arrival, the FBI discovered an alleged sympathizer of the Irish Republican Army had plans to kill her.

According to the files, a San Francisco police officer was contacted by another officer who “is a regular patron and regular acquainted with [an unidentified patron] of the Dovre Club.” The Dovre Club has a popular reputation as a republican bar and often sympathizers of the Provisional Irish Republican Army (PIRA) flocked there. The unidentified patron said that his daughter had been killed in Northern Ireland, and he wanted to secure justice by murdering the Queen.

It continued, “This man additionally claimed he was going to attempt to harm Queen Elizabeth and would do this either by dropping some object off the Golden Gate Bridge when it sails underneath or would attempt to kill Queen Elizabeth when she visited Yosemite National Park.”

During that time of the visit, there was the Troubles in Ireland. It was a 30 year conflict in Northern Ireland that divided unionists and nationalists over whether Northern Ireland should stay with the U.K. or join the Republic of Ireland. “Groups from both sides like the IRA and Ulster Volunteer Force carried out attacks, and British troops were deployed to Northern Ireland,” per People.

Despite the threat, the FBI reported that the late Queen's visit was “without incident,” and the case was closed.