A teenage soldier was leading the way with a metal detector when a bomb blast killed him, an inquest has heard.
Pte Robert Hayes, 19, of Burwell, Cambridgeshire, died in an explosion while on foot patrol in Helmand province, Afghanistan, on 3 January.
His Army colleagues gave evidence at an inquest in Wisbech.
Cambridgeshire North and East coroner William Morris recorded a verdict of unlawful killing "in the service of his country".
The inquest was told how Pte Hayes was not down to be part of the patrol on the day he was killed but had volunteered because they needed a metal detector operator.
Mr Morris said: "His family can be very proud of him and we in this country are very grateful to him."
Cpl Joseph Warren said he was just behind Pte Robert Hayes when a device went off on the staircase they were searching in a compound, killing the soldier instantly.
Pte Hayes, of 1st Battalion the Royal Anglian Regiment, was the first British serviceman to die in Afghanistan this year.
Cpl Warren and other soldiers from the patrol described how the device went off as they were searching the compound near the village of Kowshal Kalay.
The soldier said: "From what I remember, all I saw was a sharp flash in the right-hand corner of my eye.
"The flash came from where he was. I knew it had been an IED [improvised explosive device] but I didn't know then I'd been buried."
The corporal told the inquest he could move only his left hand but was able to call for help on his radio.
Pte Hayes suffered multiple, catastrophic injuries.
In a statement, the parents of Pte Hayes asked for their "brave" son's memory to be honoured.
They said he had been passionate about rugby and boxing and had played for Newmarket Rugby Club.