By Sima Kotecha
Newsbeat US reporter

Connor dreamt of being a soldier and going to West Point Military School

An American couple are warning parents in the UK about a lethal activity being played by children.

It's most commonly known as the choking game and it involves them suffocating themselves to reach a high.

Dale and Michele Galloway from North Carolina lost their 12-year-old son Connor in 2007 and say it's a craze which needs to be stopped.

His mum, Michele, said: "He was academically gifted. He loved to play football and played the guitar. He was a nice rounded child."

On a cool autumn morning in October 2007, Michele found her son with hanging from his bunk bed. He was dead.

Michele said: "His feet were maybe an inch off the floor. I just screamed."

Deaths

She says the same question ran through her head over and over again, "Why would such a happy child take his own life like this?"

After police spoke to Connor's friends at school, it was discovered that he hadn't killed himself but had died while playing a game.

It's known by several names including five-minutes-in-heaven, suffocation roulette, the choking game and involves children throttling themselves to feel good.

Doctors say it happens in two stages: First light-headedness from blocking the blood and oxygen to the brain.

Then releasing the blockage which generates a surge of blood to the brain causing the euphoria.

It's mostly done through strangling and crushing the rib cage, and is played alone, in pairs or in groups.

The activity is not sexual and is usually practised by young boys.

Dangerous

The Centre of Disease Control in the States says more than 80 American children have died over the last 10 years from doing it.

Others estimate the figure to be much higher, saying some cases are ruled as suicide with many doctors and parents not knowing about the game.

UK children's charity, Kidscape, told Newsbeat: "The Choking Game is a very disturbing dangerous activity that should not be tried.

"It is a growing craze but teenagers don't realise the serious harm this can cause."

No children in Britain are known to have died from it but a head teacher in Gloucestershire recently told the BBC that students at her school had been doing it.

Annette France works at Chipping Campden School and said: "There were a couple of other children caught copying this activity and that's when we took action with the letters home to parents."

Connor's mum and dad just want people in the UK to recognise it's happening there too.

Michele Galloway said: "People worry that if you talk about this, it brings attention to it and encourages it. That's not the case.

"It's about educating people so they know what signs to look for because it does go on."

For those seeking advice: If you know anyone who is doing it or you are trying it, please contact Youth 2 Youth via their website www.youth2youth.co.uk, where young counsellors can advise you on the dangers of the activity.