A young soldier was executed by the Taliban in Afghanistan after leaving his checkpoint to search for missing kit, an inquest heard.
After being captured, Highlander Scott McLaren, 20, was tortured, shot five times in the head with an automatic rifle and then had his body interfered with.
The soldier’s semi-naked corpse was found several hours later by British forces in a nearby river, the inquest in Trowbridge, Wiltshire, heard.
Highlander McLaren, of the 4th Battalion, The Royal Regiment of Scotland, left the safety of his base in the middle of the night to find the pair of night-vision goggles, carrying his weapon, day sack and wearing full body armour.
A comrade had left the piece of equipment at a nearby vehicle checkpoint and Highlander McLaren was the last soldier to see them.
The inquest was told, however, that when he left his checkpoint in the early hours of July 4 this year, he did not cross a bridge over a canal to get to the checkpoint but instead was caught on CCTV heading in the opposite direction.
Wiltshire and Swindon Coroner David Ridley, who recorded a verdict of unlawful killing, said it would remain a mystery as to what he was doing that night, “and sadly the only person who could help us is no longer with us”.
The inquest heard that Highlander McLaren, who was from Edinburgh, was last seen by a comrade shortly before 2am, having finished sentry duty.
CCTV shown at the inquest last captured Highlander McLaren at 2.29am and he was reported missing an hour later by colleagues preparing to go out on patrol.
A couple of weeks before his death, the soldier – who set himself high personal standards – had been spotted by Sergeant Finn Beary “welling up and a bit emotional”.
“He initially said nothing was wrong but I knew something was wrong,” Sgt Beary told the inquest. “All of a sudden he came out with ‘I keep messing up’.
“I said ‘You’re only a young lad and this is your first tour’. I said everyone messes up.
“He just didn’t give any indication what he was messing up.
“Half an hour later... he seemed back to his normal self. It seemed like he had been putting a lot of pressure upon himself.”
Captain Calum MacLeod, commanding the Scots detachment at Checkpoint Salaang, told the hearing that after the night-vision goggles disappeared the men had gone to look for them.
After not finding them, he spoke to the soldiers collectively about the importance of looking after equipment and they had also received a reprimand from Corporal Douglas Young, second in command. He stressed, however, that no one soldier was to blame for the loss.