A “senior soldier” in the US Army has been arrested in Britain over “serious” allegations as part of an investigation by UK Counter Terrorism Policing (CTP).
FBI director Kash Patel said the case “involves allegations of espionage” related to Russia, and was “of the utmost concern” to the Unites States.
The 41-year-old service member was arrested in Gloucestershire on Tuesday. He remains in custody at a London police station.
Brig Gen Sean Stinchon, commanding general of US Army Counterintelligence Command, described the suspect as “a senior soldier, entrusted with sensitive information”.
The man was arrested on suspicion of offences under Section 1 and Section 3 of the National Security Act 2023.
Section 1 refers to a person obtaining or disclosing protected information, while Section 3 refers to assisting a foreign intelligence service.
The man was reportedly arrested at Imjin Barracks in Innsworth, near Gloucester, according to the BBC. This site serves as headquarters for Nato’s Allied Rapid Reaction Corps (ARRC), the largest Nato base in the UK.
CTP has been carrying out the investigation in collaboration with American authorities, the US military and the FBI.
Officers are searching two locations in Gloucestershire, the Metropolitan Police said. Deputy Assistant Commissioner Vicki Evans of CTP added: “The allegations are serious and our investigation is very much ongoing.”
Police said the allegations relate to Russia and the investigation is not linked to any other ongoing CTP investigations.
The investigation is being led by officers from CTP London.
Patel said: “While this investigation is continuing, I want to send a clear message – this FBI has no tolerance for anyone who breaks their oath to the United States and whose actions endanger our national security and that of our partners.
“This matter shows that partnerships are essential to protect our countries, and I want to express my thanks to UK Counter Terrorism Policing, MI5, UK Defence Counter Intelligence, and the US Army Counterintelligence Command for their outstanding work.”
Brig Gen Stinchon said the allegations were “a sobering reminder that insider threats are real and persistent”.
On Monday, the US military reportedly evacuated aircraft from RAF Mildenhall in Suffolk following an alleged threat from Iran. The exact nature of the threat, including whether it is an imminent risk or a more general response, is not yet known and remains under discussion among US officials.
It comes weeks after the US withdrew its bombers from RAF Fairford in Gloucestershire following a suspected Iran-related terror incident near the air base.
There has been no suggestion that Tuesday’s arrest was linked to either of these bases, or previous incidents.
Evans said: “This significant arrest and investigation is a result of close collaboration between UK and US authorities. This activity demonstrates the strength of our UK and US law enforcement and national security partnerships, and I commend the work of all the teams involved.
“We will work together to take robust action against those we suspect of any criminal activity that could undermine our national security.”
The Allied Rapid Reaction Corps at Imjin Barracks has been contacted for comment.