Two Latvian men have been arrested under the National Security Act after a fence was breached at an RAF base in Cambridgeshire.

The alert was raised when a Ministry of Defence Police (MDP) security patrol at RAF Molesworth identified an abandoned vehicle at about 22:00 BST on Wednesday.

After searches by the MDP and Cambridgeshire Constabulary, a small breach of a perimeter fence was identified a few hours later.

The two men, who the Met Police said lived in the UK and were aged 36 and 32, were arrested inside the base perimeter.

They were initially arrested on suspicion of trespass on a prohibited site and criminal damage and taken to a Cambridgeshire police station.

The pair have since been further arrested on suspicion of an offence under section 4 of the National Security Act 2023, external – namely entering a prohibited place for a purpose prejudicial to the UK.

Counter-terror police are investigating, and they are not currently linking it to the high-profile incident at RAF Fairford in Gloucestershire, but are understood to be keeping an open mind.

Commander Helen Flanagan, head of Counter Terrorism Policing London, said: “We’re very aware of the recent heightened interest and concern around military sites, but at this stage there is nothing to suggest this incident is connected to the events at RAF Fairford last week.”

Officers said they were carrying out two searches at addresses in the Peterborough area in connection with the investigation, which Flanagan said was in the “very early stages”.

“A big part of this is looking at any potential motivation as to why the men were present at the site, but I must stress we are keeping an open mind at this stage,” she said.

“As ever, I would ask the public to remain vigilant and if you see anything of concern, then to contact police.”

The abandoned vehicle found near the perimeter of the base initially led to the partial closure of the A1M and several other roads in the Glatton area at about 13:00 BST on Thursday.

A cordon was put in place while it was examined by bomb squad officers but the roads were reopened shortly after as Cambridgeshire Police said “nothing of concern was identified”.

RAF Molesworth is located west of Huntingdon, close to the border with Northamptonshire.

In 2024, the US Defence Intelligence Agency said it had broken ground on a $556m (£421m) facility at the site – which would serve as a hub for US military intelligence in Europe and Africa.

It is also home to a Nato intelligence hub.

A Ministry of Defence spokesperson said: “We remain highly vigilant to potential threats against defence sites and work closely with the police and our allies to keep them secure.

“The protection of our bases is kept under constant review, with a multi-layered approach that includes physical barriers, patrols, surveillance, monitoring, and counter-drone capabilities.”

A spokesperson for US European Command thanked UK agencies for their support, but added: “It is inappropriate to discuss matters of intelligence, and we will not discuss specific force protection measures.

“We will continue to assess the threat environment surrounding our installations and take appropriate actions to protect our people, our platforms, and the bases where our forces operate from.”

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