A promising young cadet who had a bright future ahead of him had his life snatched away by drugs, an inquest heard.

Last night, the mother of 18-year-old former Oxfordshire sea cadet Christopher Preece said she would do "absolutely anything" to prevent others going through what her family had experienced after her son died from a heroin overdose in 2007.

It was probably his first experience with the drug.

Emma Preece, 33, from Laburnum Grove, Didcot, said her son — a top cadet, musician and chef — was "never the same again" after moving into sheltered housing where he developed a drugs habit that would later prove fatal.

Christopher's grandfather Keith said the former St Birinus School pupil was "gifted at everything he put his mind to".

When he was 16 he was recognised for his outstanding service to the cadet movement and appointed a Lord Lieutenant Cadet by Sir Hugo Brunner.

After growing up with his mother, but also living with his grandparents in North Bush Furlong, Didcot, Christopher applied to move into sheltered accommodation in Great Western Drive after lying to the authorities he was homeless.

His mother Emma said: "It all started to go wrong once Chris moved into the housing project in Great Western Drive.

"Drugs can wreck a young person's life. I want as many young people as possible to know how they ruined Chris's life. I would willingly talk to pupils at schools to show just how much it changed Chris if it saved someone else going through this."

Mr Preece, 65, a retired engineer, added: "Young people see the likes of Amy Winehouse taking drugs and think they'll do it too and it'll be okay, but that's far from the case."

Oxfordshire Coroner's Court heard that on March 1 last year Christopher and another flatmate spent the evening smoking cannabis and playing computer games.

At about midnight, Jamie Harvey said Christopher went into the bathroom during which time he believed he injected himself with heroin.

The following day friends could not wake him up, although he was still breathing. Mr Harvey said: "I tried to wake him up, but couldn't. He was snoring and making moaning noises."

Mr Harvey eventually called an ambulance at 6.30pm — but Christopher had been left lying on the bathroom floor for most of the day.

Roberto Vega, a support worker at the project, tried to resuscitate Christopher but was unable to.

A post mortem showed his death was caused by respiratory distress, brought on from pneumonia after a "substantial dose" of heroin.

Mrs Preece said: "The kids were all too afraid to call an ambulance for fear of getting a slapped wrist, but that would have been so much better than this."

Oxfordshire coroner Nicholas Gardiner recorded a verdict of accidental death.

He said: "It is possible Christopher was a fairly naive user of heroin, it was possibly the first time he had used the drug when this tragedy happened."