Andy Burnham today claimed there are ‘strong indications’ that Iran was involved in the suspected terror plot near an RAF base used by the US.

Five men were arrested on suspicion of explosives offences and terrorism after the incident close to RAF Fairford in Gloucestershire on Sunday before being bailed.

The base has been used in recent months by US bombers to launch air strikes against Iran, a fact which has been at the centre of speculation about whether it was involved in the drama, including by tasking proxies to carry out crimes on their behalf on UK soil.

Potential involvement by Iran is one of the main lines of inquiry for investigators, given that the country has used proxies in the past to carry out acts in Britain.

Iran’s London embassy has fiercely denied any involvement in the incident, but Prime Minister Mr Burnham told GB News today: ‘So what I can say is there are strong indications that Iran played a part in what happened over the weekend.

‘It is, though, still an ongoing and very serious police investigation. So I hope you’ll understand that I don’t say more at this point, but I wanted to confirm what we could say. But this will continue now.

‘It’s obviously a very serious investigation involving our colleagues in the United States, and we are working very closely with them. And I will say more when I can.

‘Obviously, I’ve been dealing with this as I’ve been here in Liverpool, we have held a Cobra meeting here during the week. We are completely on top of things, but we will say more when we can.’

The five British men are arrested near RAF Fairford in Gloucestershire early on Sunday

Police officers guard an area near RAF Fairford yesterday as roadblocks remain in place

The moment a police robot blasts the doors off one of the vans that was found near the base

A fireball bursts from the rear of one of the vans before a huge plume of smoke rises into the air

Iran’s Revolutionary Guard warned in July that any base used in strikes would be a legitimate target.

That came after the Iranian ambassador to London, Seyed Ali Mousavi, said the decision to allow American bombers to launch from RAF Fairford had become an ‘important matter for our self-defence’. 

On Sunday, the farmer who alerted the authorities said one of the three vans had suspicious lettering on the side which appeared to be fake.

The van carried branding for ‘Fuel 2You’ – unrelated to a real mobile fuel delivery company, Beaconsfield-based ‘Fuel2U’, which uses green and black branding.

It has also been noted that the phone number displayed beneath the company name – 0742 418 2599 – was spaced in a format predominantly used in Iran.

Others pointed out how it was odd to use a red logo for a business supplying fuel, when the colour of petrol pumps in the UK is green. In Iran, the colour is red.

It comes as a video revealed the moment a police robot blasted the doors off one of the vans that was found near the base.

The clip, exclusively obtained by the Daily Mail, was captured on a resident’s security camera and shows a fireball bursting from the rear of one of the white vehicles before a huge plume of smoke rises into the air.

Meanwhile, it has been revealed that one of the five men arrested over the plot had called the police before they were detained.

One of the three vans near RAF Fairford had ‘Fuel 2You’ printed on its exterior in red text

The ‘Fuel 2You’ branding raising suspicions the men may have been transporting red diesel

The three white vans are investigated by a robot after the alleged plot near RAF Fairford

A van belonging to the real company ‘Fuel 2U’ – in no way linked to the RAF Fairford incident

The suspect phoned police around an hour before a farmer said she called 999 at 1.36am on Sunday after discovering three vans blocking a road near the base. 

The five British nationals, all in their mid-20s, were subsequently arrested on suspicion of explosives offences and terrorism. 

The development again led US President Donald Trump to comment on the security operation, saying he was ‘disappointed’ about the release of the men on bail.

It has also emerged that petrol, but no explosives, was found in the vans which sparked the security alert in the village of Whelford.

US Secretary of State Marco Rubio said yesterday that the suspected plot ‘clearly involves the hand of a foreign actor’, but refused to provide further details, and Mr Trump has also said the alleged plot ‘might be’ linked to Iran.

Head of UK counter-terrorism policing assistant commissioner Laurence Taylor said yesterday that a police response was activated in the early hours of Sunday ‘due to a range of information that we received’.

Mr Taylor said the vehicles have been examined, adding: ‘We can confirm that no improvised explosive devices have been found. We have found a quantity of an accelerant, petrol, and we have recovered that as part of our investigation.’

He said the five suspects released on bail ‘remain under investigation’ and ‘must adhere to very strict conditions’.

The five suspects, all UK nationals, are a 24-year-old from Camden, north London; and a 23-year-old, two 24-year-olds and a 25-year-old from Westminster, central London.

READ MORE: Moment police robot blasts off doors of one of three white vans found near RAF base during counter-terror operation