Leigh Boobyer
Live page reporter

Here's what we know:

• Five men are currently in custody after being arrested on suspicion of preparation of a terrorist act. They were also held on suspicion of committing offences under the Explosives Act.
• Helicopter footage has revealed a wheeled robot, from the Army, is operating near three parked white vans in the village.
• A 400m cordon is in place around the vehicles while they're being examined, with 85 households evacuated to a leisure centre.
• Gloucestershire Constabulary say they received a call at about 00:45 BST relating to "three suspicious vehicles" travelling toward RAF Fairford.
• Several residents who were evacuated have told the BBC they were woken up in the night by police officers knocking on their doors.

• At a news conference, Assistant Chief Constable Richard Ocone says: "work to establish the full nature of the incident is ongoing".

James Landale
Diplomatic correspondent

We do not yet know who or what is behind the ongoing incident outside RAF Fairford. But some may suspect Iranian involvement.

The US Air Force has used the base to launch attacks against Iran since March.

Iran’s foreign ministry in July accused the UK of complicity in war crimes and gave this explicit warning: "Any party that, in any manner, participates in military aggression against Iran will bear responsibility for the consequences and repercussions of its decision."

Ongoing US and Iranian diplomacy is failing to break the current impasse in the war.

Some analysts have speculated Iran may have an incentive to escalate the conflict and impose new costs on the US for failing to agree a deal.

That could involve attacks in the Middle East but also further afield. But until we know more, this is just speculation.

People evacuated from their homes near RAF Fairford may have to stay overnight as the emergency services make the scene safe, a local councillor has said, as he described the incident as “destabilising”.

Gloucestershire County Councillor Paul Hodgkinson told the Press Association: "It’s not something we’ve encountered in Gloucestershire before in recent times, and so it is worrying."

When asked whether there had been any more preparations to protect people living near Fairford amid global conflicts, Hodgkinson added: “We are in a more heightened state of awareness around these things.”

As authorities continue their enquiries, those forced to leave their properties are being supported at a leisure centre, where overnight food supplies, provided by the council, have begun arriving.

Leigh Boobyer
Live page reporter

Assistant chief constable Richard Ocone from Gloucestershire police says the cordon is still in place "as a precaution" and "the public can expect to see an emergency services presence in the area for some time".

"The emergency services have well-rehearsed plans for dealing with major incidents," he adds.

He says residents who have been unable to stay with friends or relatives have been sent to a nearby leisure centre, with the force "working as quickly as possible" to get them back to their properties.

"We’d like to thank the residents who have left their homes this morning for their understanding and support."

“We would ask the public not to speculate but to follow official channels for updates," he adds.

Image source, Reuters

We can now bring you further details from Counter Terrorism Policing.

Deputy Assistant Commissioner Vicki Evans says they are in the "early stages of an investigation, and five men remain in custody".

Counter Terrorism are "working closely" with partners to "understand the circumstances of the incident", she says.

She adds: "We continue to work with Gloucestershire Police to keep the community safe as we work to gather evidence from the scene."

Repeating details shared earlier, she says a 400m cordon is in place around the vehicles while the Army's Explosive Ordinance Disposal unit carries out examinations, and 85 households have been evacuated.

Counter Terrorism Policing say the five men have now been further arrested on suspicion of preparation of a terrorist act.

We'll bring you more on this shortly.

Image source, POOL

We've just received an update from Gloucestershire police following a major incident near RAF Fairford.

Here's what we learnt:

• Five men were arrested on suspicion of committing offences under the Explosives Act and remain in custody
• The force received a call at about 00:45 BST relating to "three suspicious vehicles" travelling toward RAF Fairford
• A 400m cordon is in place around the vehicles while they are being examined, with 85 households evacuated
• Ocone said work is ongoing to establish the full nature of the incident, with the force working alongside counter-terror police

Assistant Chief Constable Richard Ocone finishes by stressing the police's focus is on the local community.

He thanks residents for their co-operation in evacuating, and says he appreciates the disruption this has caused.

"I would like to reassure them that we are working as quickly as we can to get them back into their properties," he adds.

Ocon then asks the public not to speculate about the incident.

That brings the brief news conference to a close.

Image source, Reuters

Assistant Chief Constable Richard Ocone says that work to establish the full nature of the incident is ongoing.

He says the force is working closely with its partners in counter-terrorism policing.

He adds that a 400m cordon is in place around the vehicles while examinations take place.

Eighty-five households have been advised to evacuate with a leisure centre open to house those unable to stay with family or friends.

Assistant Chief Constable Richard Ocone now says five men were arrested on suspicion of committing offenses under the Explosives Act.

They were taken into custody where they remain, he says.

Image source, Reuters

We've just heard from Gloucestershire police assistant chief constable Richard Ocone, who says the force received a call at about 00:45 BST on Sunday morning relating to "three suspicious vehicles" travelling toward RAF Fairford.

A woman who has lived near RAF Fairford for the last 50 years says there has been an increase in military security in recent weeks.

She told the Press Association that "very heavy vehicles" had been put across all gates, with "great big concrete walls” also placed behind some gates, including on Dunfield Loop and Whelford Road.

Image source, Getty Images

Police have been responding to the major incident since the early hours of this morning, with nearby Fairford Youth Football Club, on Horcott Road, impacted.

Posting on its Facebook page, the club said today's games had been postponed "due to circumstances beyond its control".

The post said: "Please don't head to the club."

Image source, Getty Images/Justin Tallis

Image source, Getty Images/Justin Tallis

Image source, Getty Images/Leon Neal

One resident who has lived in the area for 18 years said she was woken by police banging on her door.

She was then ordered to leave straight away, without being able to take her dog with her.

Jo says she knew it "must be serious" after she was evacuated from her home at about 07:00 BST.

"We were asleep and they were just banging on our door.

“They said it was a critical incident and we’ve got to leave straight away, and they basically wouldn’t leave the doorstep until we left.

“We just had to throw our clothes on and come. We didn’t know anything.”

Jo says the police waited at the door until they left.

“I didn’t even brush my teeth or nothing."

Jo says she had to leave her dog, Coco, after the rush.

“They just implied that we shouldn’t take him. We fed him, but it’s not about that, is it, it’s just he’s on his own for hours.”

The police news conference on the RAF Fairfield incident, which was due to start at 12:45 BST, has evidently been delayed.

Our reporters are waiting for a spokesperson for either Gloucestershire or counter-terror police to arrive. We will update you when we hear more.

Jonathan Beale
Defence correspondent

A British Army bomb disposal team – known as an Explosive Ordnance Disposal team – is still carrying out operations, according to a defence source.

Pictures from a news helicopter show a remote controlled robotic system being used to inspect a number of stationary white vans in the area.

A defence source said UK Military Police were also supporting their civilian counterparts in providing a security cordon around the area.

Leigh Boobyer
Live page reporter

While we wait for police to give an update on the major incident - here are how things look on the ground.

Image source, PA Media

Armed police are placed on roads around RAF Fairford while investigations continue

Image source, Reuters

Some residents in the village have been evacuated to a leisure centre and have not been told when they can leave

Image source, Reuters

Emergency services have been positioned in and around the village since the early hours

Image source, PA Media

Counter-terrorism police are leading the investigation

Image source, PA Media

Gloucestershire Police say several men had been arrested on suspicion of offences under the Explosives Act.

While we wait for police to give us their update, the cordon, which has been in place since the early hours of this morning, has been expanded to include RAF Fairford.

Our reporter Alastair McKee says everyone has been moved out of the vicinity of the air base and into the village further down the road.

We're expecting to hear an update from authorities shortly.

You'll be able to watch live at the top of the stream when the conference gets under way.

We'll bring you all the key news lines here, too.