The incident took place on October 13 but was first reported on Sunday by British tabloid, The Sun. Thames Valley Police confirmed last month's theft in a statement to CNN on Monday.
Police said the burglary was reported at around 11:45 p.m. (6:45 p.m. ET) and that the perpetrators entered a farm building on royal land. The suspects "made off with a black Izuzu pickup and a red quad bike," the police statement said, adding that no arrests have been made and an investigation is ongoing.
The Sun reported that two masked men scaled a 6 ft (1.83 meter) fence to enter the Crown Estate land, then used the stolen truck to smash through a security gate and flee the scene.
Though Windsor Castle is one of King Charles and Queen Camilla's residences, the pair were not staying at the castle at the time of the reported burglary. Charles was in Scotland and didn't return to London until the following day.
The Prince and Princess of Wales and their three children live at Adelaide Cottage, a four-bedroom Grade II listed house which is also in the grounds of Windsor Castle, and would likely have been at home on the night of the security breach.
Buckingham Palace told CNN it never comments on security matters, as did Kensington Palace.
On Christmas Day 2021, a man broke into the grounds of Windsor Castle armed with a crossbow in an attempt to assassinate Queen Elizabeth II, who was in the royal residence at the time.
The late Queen was unharmed, although the intrusion sparked serious questions about palace security, especially when it emerged that her repeated attempts to summon help were ignored.
Jaswant Singh Chail, who was 19 when he attempted to kill the Queen, was sentenced to nine years in jail in 2023.
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