Shropshire airman Brent McCarthy pictured with his murderer

Seconds after the picture was taken the Afghan and another gunman turned on both 25-year-old Corporal McCarthy and his comrade, Lance Corporal Lee Davies, a military inquest heard.

Corporal McCarthy and 27-year-old Lance Corporal Davies, of the 1st Battalion Welsh Guards, died of "unsurvivable injuries" from close range gunshots, the inquest at Oxfordshire Coroners Court was told yesterday.

And the Afghan national in the picture, released to the Shropshire Star by Corporal McCarthy's family, was shot dead by a British guardsman as he tried to flee the scene.

The men had been engaging in "banter and general chit chat" with what they thought were two Afghan Uniformed Police officers as they guarded a base in Lashkar Gah in May 2012.

The inquest heard that that Lance Corporal Davies had remarked that the Afghan pictured had "wet himself" and this may have been a sign as to what was about to happen.

Despite desperate efforts to resuscitate Corporal McCarthy and Lance Corporal Davies after the shooting, "there was nothing colleagues, combat medics or medical staff could have done", a report by home office pathologist Dr Russell Delaney concluded.

Ballistics experts found Corporal McCarthy had been struck by "four high velocity projectiles" shot at "close or contact range".

The former Lilleshall Primary and Orleton Park pupil joined the RAF police in 2008.

He was assigned to the base in 2009 where he volunteered to deploy with 174 Provost Company, 3rd Regiment Royal Military Police, where he helped train and mentor Afghan police. His body was flown to the RAF Brize Norton in Oxfordshire and his flag-draped coffin carried by six soldiers from the aircraft and saluated as it was put into a waiting hearse.

Hundreds of mourners paid their respects as Corporal McCarthy was buried with full military honours at St Nicholas's Church, Codsall.

By Jennifer Meierhans in Oxford

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