Police are believed to have the DNA of at least one of two attackers who tried to bundle an RAF serviceman into a car at knifepoint after he beat one of them so badly he was left with blood on him.

The victim is said to have fought back when two men of Middle Eastern descent tried to abduct him at RAF Marham, the motive for which Norfolk Police said they were 'unable to discount terrorism'.

Reports have surfaced among those living on the base that police have taken a swab of DNA from the serviceman in question after he was left with the blood of one of his attackers on him.

RAF personnel have now been warned to 'keep a low profile' and told not wear their uniforms in public after the attempted abduction and knife attack outside a military base.

The two knifemen, who were described by police as being of 'Middle Eastern descent', are now on the run after attempting to abduct the airman, who was running outside RAF Marham, near King's Lynn, Norfolk, which is home to jets bombing the so-called Islamic State.

Norfolk Police (pictured today) said they were 'unable to discount terrorism' as a motive for the attempted knifepoint abduction of a serviceman by two men of Middle Eastern decent at RAF Marham

RAF personnel have now been warned to 'keep a low profile' and told not wear their uniforms in public after the attempted abduction and knife attack outside a military base

The base was placed on lockdown after the serviceman was approached by the blade-wielding assailants at around 3.30pm yesterday.

Norfolk Police today described how the victim was a married serviceman in his late 20s who was out jogging when he was approached by two men between 2.55 and 3.26pm on Wednesday.

The first suspect apparently shouted at him and made an attempt to grab him by the shoulder and wrist but the victim successfully fought him off, causing the suspect to fall to the ground.

The second man then approached the victim but on noticing his accomplice on the ground went towards him instead, at which point the victim ran off.

The second man was armed with a military-style knife with a 2.5inch blade which has not been located.

A planned family fun day is still going ahead at RAF Marham today despite last night's attack

Numerous air flights have taken place today including a Tornado flypast and a performance by the RAF Falcons

The suspects fled the scene in a dark-coloured people carrier and have not been located.

The victim was said to be 'very, very shaken following his ordeal.' He was not in uniform at the time and was not wearing clothes which would identify him as a member of the military.

Police described the first suspect as being between 20 and 30 years old, approximately 6ft tall, of athletic but stocky build, with dark hair which was long on top and had a well-groomed beard.

He was of Middle Eastern origin in appearance with a dark skin tone and wore dark casual clothing.

The second suspect is described as between 20-30 years old but younger than the first suspect and of a slimmer build. He was approximately 5ft 10 and clean shaven with short dark hair.

Detective Superintendent Paul Durham (pictured), from the Norfolk and Suffolk Major Investigation Team, said: 'I can confirm we are treating this as an attempted abduction and detailed enquiries are being carried out at the scene to establish the full circumstances'

A 'heightened' police presence remains around an RAF airbase today as officers continue to hunt for the two men who fled the scene in what is believed to be a dark coloured Ford Galaxy

He was also of Middle Eastern origin in appearance and wore a white t-shirt and dark shorts, police said.

Detective Superintendent Paul Durham, from the Norfolk and Suffolk Major Investigation Team, said: 'I can confirm we are treating this as an attempted abduction and detailed enquiries are being carried out at the scene to establish the full circumstances.

'The motivation for the attack remains unclear at this time, and whilst we are currently unable to discount terrorism, there are a number of other possible hypotheses.

'We are therefore carrying out a thorough investigation to understand what has happened, why and who is responsible.

'Visible patrols continue in the area and officers will be carrying out house-to-house enquiries and detailed searches of the scene in Squires Hill, which remains closed for the time being.'

Two men threatened a serviceman outside RAF Marham, near King's Lynn, Norfolk, pictured

A 'heightened' police presence remains around an RAF airbase today as officers continue to hunt for two men who fled the scene in what is believed to be a dark coloured Ford Galaxy

Det Supt Durham added: 'I'm keen to hear from anyone who may have seen the vehicle described above in the King's Lynn area but particularly towards Marham between midday and 6pm yesterday and would urge anyone with information, no matter how insignificant it may seem to them, to call police on 101 or call Crimestoppers anonymously on 0800 555 111.'

A planned family fun day is still going ahead at RAF Marham today despite last night's attack.

Numerous air flights are expected to take place, including a Tornado flypast and a performance by the RAF Falcons.

Families began arriving at the base at around 9am and were directed by groups of air cadets.

Armed officers stood guard at the barrier and paired up patrols wandered around outside of the main entrance wearing camouflage and black protection vests.

A police van was parked up outside the general car park today where visitors were being asked to show identification before being allowed to enter.

Police would not comment on whether the incident was terror related but a source said that there was a 'strong possibility' this was a terror attack, adding 'this could've been a lot more serious'

A road near the base remained closed overnight as the police investigation into the attack got underway

Following the alleged abduction attempt, nearby residents had been told not to talk to reporters via leaflets pushed through their doors.

They were also told not to post anything on social media but said a helicopter had been circling above after the incident and numerous police cars attended the scene.

Families were reluctant to comment on the incident as a number of them had travelled in for the event.

A 'heightened' police presence remains around an RAF airbase today as officers continue to hunt for the two men who fled the scene in what is believed to be a dark coloured Ford Galaxy.

Personnel who work at the airbase were advised to be vigilant following the incident.

An internal memo sent to staff by Rich Curzon, in Protective Security at the MoD, said: 'Following a security incident at RAF Marham, it is directed that all personnel keep a low profile and not make themselves vulnerable.

At least one road near the base was locked down after reports of the attack outside an RAF base

'Specifically, until the threat subsides, no-one is to be on their own on foot, or on a bicycle, within the local area in uniform or clothing which might identify them with the military.'

A further information note to all personnel described the incident as an 'alleged attempted abduction' and explained the incident occurred when a serviceman had been running 'approximately one mile outside of RAF Marham's main gate.'

Police remain around the airbase in the form of 'reassurance patrols' to support local residents who work there.

Inspector Nathan Franklin, of Norfolk Police, said: 'Police have closed the road close to the RAF Marham Airbase.

'A man was approached by two men in the Burnthouse Road and Ladywood Road area and threatened with a knife just before making off in a car like a Ford Galaxy.'

He added that the investigation was ongoing.

An MoD spokesman said: 'We are aware of an ongoing police operation in relation to an incident near RAF Marham.

'It would be inappropriate to comment further at this stage.'

Forensic expects are expected to work in the area today, which is likely to remain cordoned off.

Police and Crime Commissioner for Norfolk, Lorne Green said we 'must not draw any conclusions' as investigations are in their early stages.

'The incident is under close investigation at the moment with an open mind,' he said.

'There is nothing at the moment to strongly suggest one motive above another and it is all subject to a very intensive investigation at the moment. *

'Incidents of this kind are very rare in our county and our constabulary, working in co-operation with other forces, are well-equipped to respond to any eventuality of violent crime, regardless of motive.

'There is a very close co-operation between the constabulary and the military police, which is ongoing at the moment.'

Meanwhile a families day being held at RAF Marham today will go ahead as planned, a spokeswoman for the base said.

The ticketed event, which is not open to the public, allows families and friends of servicemen and women to see the base and enjoy displays from aircraft.

Tornado bombers from the base have been deployed to carry out air strikes against Islamic State targets

The base is home to four squadrons of Tornado bombers which have been flying bombing raids against Islamic State fighters in Syria since December from a base in Cyprus.

It is also home to almost 10,000 people, including members of the RAF, Navy and Army, as well as the civil service and other staff.

RAF Marham was originally opened in August 1916 as a military night landing ground on an 80-acre site within the boundary of the current grounds.

The station is one of few large enough for the operation of United States Air Force Boing B-52, and a number of these aircraft visited on exercises in the 1970s and 1980s.

Six Wings and five RAF squadrons are currently stationed at the base, with approximately 4,500 people employed there.

From 2018, the UK fleet of F-35B Joint Strike Fighter aircraft will be based at RAF Marham and it is due to be provided with £300m by the Ministry of Defence, for new and enhanced infrastructure.

The aircraft will be operated by 617 Squadron of the Royal Air Force (Dambusters) and 809 Naval Air Squadron of the Royal Navy's Fleet Air Arm.

In 2013, Drummer Lee Rigby was killed outside Woolwich barracks, south-east London by two men who said they were avenging the killing of Muslims by British armed forces.

They were later jailed for life.