A coroner has warned of the dangers of ski lifts after a British teenager died during a school trip to the French Alps.
Kieran Brookes was strangled when his backpack became entangled in a ski lift in the Alpine resort of Chatel in February 2011.
The 14-year-old, from Bovey Tracey, Devon, was suspended 50ft in the air for around four minutes before he was freed.
Rescuers attempted to revive the Torquay Boys' Grammar School pupil, before he was taken to a hospital in Annecy, France, with a severe brain injury.
He was transferred to the Royal Devon and Exeter Hospital, where he died on 17 March, 2011.
Two years ago, lift operator SAEM Sports et Tourisme a Chatel, was cleared of involuntary manslaughter by a French court.
But lift supervisor Richard Cettour was convicted of the charge and given a six-month suspended prison sentence.
The court heard Cettour was not at his post during the accident and was found not to have reacted to other skiers calling for him to hit the emergency stop button.
John Tomalin, deputy coroner for Exeter and Greater Devon, recorded a conclusion of unlawful killing and said he will write a 'preventing future deaths' report to Devon County Council and Torbay Council to highlight the dangers of ski lifts.
"Kieran Brookes died as a result of unlawful killing because appropriate mechanisms were not in place to halt the ski lift in time," he said.
"There were inadequate and inconsistent warning signs about the dangers of wearing backpacks on chair lifts."
During the inquest in Exeter, teacher Charlotte Pittocho said she had not heard anyone tell skiers to remove rucksacks when getting on the ski lift.
She said Kieran had got on the lift ahead of her, but she was not aware of a problem until the lift stopped and a siren went off.
"From where I was sat the boy had his back to me and he was continuing to struggle.
"I could see he was now unconscious and looked like a doll. At this point I was really upset and it was really traumatic to watch."
Fellow teacher Nina Shinner said if a member of a staff had been sat with Kieran, they would still have been unable to prevent the accident.
"You need an operator to stop a chair if there is an incident," she said.
A post mortem examination found Kieran died from pneumonia as a result of a hypoxic systemic brain injury.
After the inquest verdict, Kieran's parents said: "We have been waiting for six years to finally hear answers to many difficult questions we have been grappling with over the tragic loss of our son.
"We hope that after today's verdict the stark warnings which have been heard, will finally be listened to and save another family from facing the same tragedy."