Earlier, a local farmer recounted how she had seen a group of hooded and masked men early Sunday.

“When they saw me they ran ahead of me — some into the field and some towards the neighboring village,” the farmer, speaking on condition of anonymity, told the BBC News on Monday. “I then realized that something highly unusual was taking place.”

Asked if British authorities knew of the threat ahead of time or only became aware after being called by a concerned farmer as has been reported, British Defense Minister Wes Streeting told U.K. broadcaster Sky News Monday that the member of the public “did the right thing” and acted quickly.

A grainy image has also emerged appearing to show the suspects.

The photo, which began circulating on social media Sunday morning, shows five men sitting on the ground topless and apparently handcuffed. They are flanked by armed officers.

The image geolocated to near RAF Fairford by NBC News. NBC News could not locate the original source of the photo.

The suspects remain in custody, Evans said, as investigators probe a possible motive. Their names have not been released.

Another image showing three white vans near the air base has also circulated online.

Fuel2U, a U.K. fuel delivery company, said in a statement that a version of its logo appeared on one of the vehicles, adding that neither the vehicle nor any of the individuals involved has any connection to it.

“We are extremely concerned that our company’s name has been used without our knowledge or permission,” the statement said.

Early on, the operation prompted questions about a possible link to Iran.

In March, 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 ⁠Islamic Revolutionary Guard Corps warned Britain that “any base used to facilitate aggression against Iranian territory is considered a legitimate target,” Iran’s semiofficial Tasnim news agency reported, specifically citing bomber aircraft flights taking off from Fairford.

There has been no immediate reaction from Iran. NBC News reached out to the Iranian embassy in the U.K. for comment, but didn’t immediately receive a response.

“I am very aware of the levels of speculation about the motivation behind this incident, and the geopolitical questions that are being raised,” Evans said, adding that investigators should be “given the space to work carefully and clearly.”