Police have reportedly foiled a suspected terror attack on soldiers protecting King Charles in what has been described as a “huge security scare”. A man was arrested on separate offences before police discovered his alleged plan while he was in custody. The arrest came as soldiers at Victoria Barracks near Windsor Castle, Berks, were reportedly warned not to leave the grounds in uniform. A source told The Sun: “The suspect is feared to have been plotting an attack.

“Police informed bosses at the barracks and measures were taken immediately despite him already being in custody. It was a huge security scare. But it was in the interests of everyone’s safety.” Victoria Barracks is only a few hundred yards from Windsor Castle and is the home of the 1st Battalion Coldstream Guards. It’s understood the Ministry of Defence (MoD) is “aware” of the incident. British soldiers are trained to always exercise high levels of personal security.

The Sun reports Thames Valley Police first arrested the 20-year-old suspect on suspicion of possessing an offensive weapon and arson at the Salt Hill Activity Centre. It’s understood the man is a “lone actor” and no other arrests have been made.

However, while in custody he was re-arrested on suspicion of preparation of terrorist acts on Sunday June 1, and the investigation is now being headed up by Counter Terrorism officers.

The Daily Express hs contacted the Ministry of Defence for comment.

The arrest comes as King Charles made a trip to the headquarters of the Royal Artillery this week.

His Majesty was met with a 21-gun salute as he arrived at the headquarters of the Royal Regiment of Artillery at Larkhill, Wiltshire, in his first visit since assuming the title of Captain General.

The King, who became ceremonial head of the regiment following the death of Queen Elizabeth II, received the royal salute as he arrived at the regiment’s headquarters near Salisbury where he was met by Master Gunner, St James’s Park, Lieutenant-General Sir Andrew Gregory.

Following the national anthem, Charles, wearing the number four tropical dress uniform, was invited into the officers’ mess where he met personnel including representatives from the newly formed King’s Gurkha Artillery (KGA).

In the dining room, the King had a chance to see historical artefacts including the voluntary artillery officer full dress tunic uniform of his great-grandfather George V.

Charles commented: “It’s lasted very well.”