Americans warned to ‘exercise caution’ in UK after farmer foils terror plot at UAF base

"US citizens are encouraged to exercise caution and be mindful of personal security. US citizens are advised to follow instructions of local authorities for their personal safety and security," and, "We remind US citizens that UK authorities rate the threat of terrorism in the UK as severe. US-associated facilities, gatherings, and organizations may be at heightened risk," the US embassy in the UK stated.

Five men have been arrested on suspicion of preparing a terrorist attack after three suspicious vehicles were spotted traveling toward a British air base used by the US military for strategic bomber operations, authorities announced Sunday.

President Donald Trump said the suspects had been under investigation and were planning to “do big damage” to the installation.

“We had them under investigation,” Trump told reporters. “They were looking to do big damage to our fort.”

Trump added that authorities “had them under view for a long time” and said American officials had worked with British authorities to apprehend the suspects.

According to an official statement from Counter Terrorism Policing, authorities received a call at approximately 12:45 am Sunday reporting three suspicious vehicles that appeared to be traveling toward RAF Fairford in Gloucestershire.

A call was made by a local farmer driving home from a party in the early morning hours and who came upon suspicious activity, reported by the Telegraph. She stated, "I just thought what the h*ll are they doing… I saw a group of Middle Eastern-looking young guys running off through the trees. Some of them had masks or balaclavas on, and they all scattered ahead of us as we drove back past."

Armed officers responded and arrested five men in the Whelford area on suspicion of offenses under Britain's Explosives Act. The suspects were subsequently arrested on suspicion of preparation of a terrorist act under Section 5 of Britain's Terrorism Act.

“We are in the early stages of an investigation, and five men remain in custody,” Counter Terrorism Policing Senior National Coordinator Deputy Assistant Commissioner Vicki Evans said.

Authorities established a roughly 400-meter cordon around the vehicles while the British Army's Explosive Ordnance Disposal unit examined them. Approximately 85 households in the surrounding area were evacuated as a precaution.

Reuters reported that a source familiar with the investigation said an Iranian-linked motive was the leading theory being examined by investigators. According to the report, authorities were also considering whether the incident could be connected to Russian sabotage activity or an Islamist terrorist plot.

Britain's defense secretary was specifically asked Sunday whether Iran was involved and declined to make such a determination while the investigation remained underway.

The possibility of an Iranian connection comes amid heightened tensions surrounding RAF Fairford. The installation has taken on increased strategic importance during the conflict with Iran and has been used by American forces during operations involving Iranian targets. Iran's Islamic Revolutionary Guard Corps previously warned that military bases used to launch attacks against Iranian territory could be considered legitimate targets.

A local official also told Reuters there had been a specific Iranian threat involving Fairford approximately six weeks before Sunday's arrests, prompting increased surveillance around the installation.

RAF Fairford is a strategically important American military installation in Europe. The US Air Force identifies Fairford as the “preferred bomber forward operating location in Europe” for US Air Force Global Strike Command. The Air Force has also described the installation as Europe's premier forward bomber base.

“RAF Fairford is built for bombers,” Air Force Maj. Richard Mutari, assistant director of operations for the 420th Air Base Squadron, said in a previous Air Force release.

The base has hosted B-52 Stratofortress strategic bombers as part of US Bomber Task Force deployments and supports American global-strike operations throughout Europe. Fairford is also located near RAF Welford, which the US Air Force says is the second-largest conventional munitions storage area in Europe and primarily supports operations at Fairford.

British authorities have not publicly identified the five suspects, disclosed their nationalities or announced a motive. There has been a report that 5 UK nationals based in London are suspected of being involved, according to SkyNews.