According to recently revealed FBI records, Queen Elizabeth II was the target of a possible murder attempt in 1983 while she was visiting the US.
In the wake of the late Queen's passing last year, the Federal Bureau of Investigation made a number of documents on her trips to the US public.
They demonstrate how the FBI was concerned about IRA threats while assisting in securing the monarch's safety during her travels.
A San Francisco police officer received the death threat.
The file states that a federal agent was alerted about a call from a man that a police officer who frequented an Irish pub in San Francisco had met there.
According to the police, the man claimed to be seeking retribution for his daughter who "had been killed in Northern Ireland by a rubber bullet,
On February 4, 1983, a month or so before Queen Elizabeth II and Prince Philip's trip to California, the threat was made.
The statement in the paper reads, "He was going to try to hurt Queen Elizabeth and would either do this by dropping something off the Golden Gate Bridge onto the Royal Yacht Britannia when it sails underneath, or would try to kill her when she visited Yosemite National Park."
The Secret Service had prepared to "close the walkways on the Golden Gate Bridge as the yacht nears" in reaction to the threat. It is unknown what steps were taken in Yosemite, but the trip nevertheless happened. The FBI did not release any information regarding the arrests.
Following a FOIA request made by US media outlets, the 102-page cache was posted to the FBI's information website, the Vault, on Monday.
A considerable lot of the late Sovereign's state outings to the US, for example, her excursion toward the West Coast in 1983, occurred while strains encompassing the Difficulties in Northern Ireland were at their most noteworthy.
The late Sovereign went to the American Bicentennial festivals in 1976 while she was in New York City.
The reports make sense of how a pilot was given a request for flying a light plane over Battery Park while holding a notice that read, "Britain, Escape Ireland."
The records show how the FBI kept a careful watch out for what it accepted to be certified dangers against the late Sovereign.
Ruler Mountbatten, her subsequent cousin, died in a 1979 IRA blast off the shore of District Sligo in the Republic of Ireland.
In front of an individual visit by the late Sovereign to Kentucky in 1989, an interior FBI reminder read "the chance of dangers against the English Government is ever-present from the Irish Conservative Armed force (IRA)".
It proceeded with that "Boston and New York are mentioned to stay alert for any dangers against Sovereign Elizabeth II with respect to IRA individuals and quickly outfit same to Louisville," in Kentucky.
The late Sovereign, who claimed racehorses, is known to have visited Kentucky a few times during her life to partake in the state's equestrian features, including the Kentucky Derby.
On a state visit in 1991, the late Sovereign was planned to see a Baltimore Orioles ball game with President George H Shrubbery.
The FBI cautioned the Mystery Administration that "Irish gatherings" were arranging fights at the arena and "an Irish gathering had held an enormous block of show off passes" to the game.
The department let NBC News know there may be "extra records" that exist other than the ones delivered for the current week, however it didn't set out a plan for their distribution.
