sentenced to jail but it is not known how long he will serve or if he is still in custody.

Curley's widow, Kirianne, 28, only learned of the teenager's apparent involvement shortly before the hearing.

Lieutenant Colonel Paul James, who was in charge of operations with 40 Commando Royal Marines at the time, said: "I received a report from the Afghan national police that a 14-year-old boy had been handed in by his father for being the trigger man in an IED attack."

James said the date corresponded to the day Curley was caught in the explosion in May last year. He added: "The father was concerned that his son was embarking upon a life as a fighter with the Taliban and feared for his life.

"He said Aga Wali had beentold he would be paid 80 US dollars but when he went for payment they said aggressively he should be fighting for ideological reasons and not financial gain.

"Aga Wali left angrily and felt betrayed. The boy was detained briefly within the national directorate of security before being processed through the courts and a sentence of imprisonment was imposed of an uncertain period of time." Another witness, Captain Dom Rogers said he was present when the boy was questioned. "In my presence he admitted activating an IED and acting as the trigger man. He was unable to read a map but was able to describe the ground and it fitted with that where Corporal Curley was wounded fatally," he said.

The fatal patrol was organised as part of an effort