LONDON — British police arrested several men on suspicion of explosives offences on Sunday near an air base which the United States Air Force had been using to facilitate strikes on Iran.

A major incident was declared, with a large emergency services presence seen in the area around RAF Fairford, close to the village of Whelford in west England.

“A number of properties are currently being evacuated,” the Gloucestershire Police force said in a statement, following the arrest of “several men on suspicion of offences under the Explosives Act.”

“The Army’s specialist explosive ordnance disposal team are currently examining a number of vehicles,” the police statement added.

Police, who did not confirm any link between the incident and the base, said they believed the incident to be “contained.”

The Reuters news agency had reported that security measures at the air ‌base have been significantly increased in recent ‌days. A spokesperson for the U.S. ‌Air Force told the agency they would not discuss specific force protection measures.

“The 501st Combat Support Wing and our fellow ⁠UK-based Wings remain vigilant and ⁠will take appropriate actions to ensure the safety and security ‌of our US service members, civilians, contractors, and their families,” the spokesperson ‌said, ahead of the police statement.

“We constantly assess ⁠a variety of factors that determine what measures we institute or modify to protect our installations, our people and their families,” they added.

In March this year, Britain’s then-prime minister Keir Starmer gave permission for the U.S. to use its bases for “specific and limited defensive” operations against Iran.

In July, Iran’s ⁠Revolutionary Guards warned Britain that “any base used to invade Iranian territory is our legitimate target,” Iran’s semiofficial Tasnim news agency reported, citing bomber aircraft flights from Fairford.

At the time, a British government spokesperson said that the country was “ready to keep the United Kingdom safe from any kind of attacks, whether it’s on our soil or from abroad.”