Police say nothing so far suggests the incident at RAF Molesworth is linked ​to events surrounding RAF Fairford last month.

Two Latvian men have been arrested inside a military base in southeast England that houses United States and NATO intelligence hubs after the perimeter fence was breached, police have said.

The arrests come amid heightened concerns about security at military bases in the United Kingdom after a separate incident last month.

Counterterrorism police said on Thursday that the two men, aged 36 and 32, were arrested at the Royal Air Force (RAF) Molesworth base in Cambridgeshire.

They are being held on suspicion of trespass and of entering a prohibited place “for a purpose prejudicial to the UK”, said police.

A security patrol had spotted an abandoned vehicle near the base late on Wednesday night. Police found a “small breach” in the perimeter fence before locating and arresting the men in the early hours of Thursday, they said.

The men were taken to a police station in Cambridgeshire where they are still in custody. Both are Latvian nationals residing in the UK.

The arrests come after a major incident at RAF Fairford in western England on September 27 that led to the arrest of seven men, all in their 20s, who have since been released on bail. One is a dual UK-Iranian national.

No connection to RAF Fairford

Due to the nature of the incident, UK counterterrorism police are leading the investigation into the security breach, police said.

“We’re very aware of the recent heightened interest and concern around military sites,” said Commander Helen Flanagan, head of Counter Terrorism Policing London.

“But at this stage there is nothing to suggest this incident is connected to the events at RAF Fairford,” she added.

Flanagan said that the investigation at RAF Molesworth is at an early stage but added that enquiries would home in on “any potential motivation as to why the men were present at the site”.

RAF Molesworth, formerly a World War II airbase, is now a non-flying facility managed by the United States Air Force.

US intelligence has based its operation centres for Europe and Africa at the base near Huntingdon. It is also a NATO intelligence hub, according to a Central Intelligence Agency (CIA) website.

On Sunday, US military planes were abruptly flown out of the RAF base at Fairford in Gloucestershire, after three suspicious vehicles were seen near the base, prompting a major incident to be declared.

That base had been used by the US military to conduct strikes in its war against Iran.