Doctors suspect the suicides of some children may really have been caused by them accidentally choking themselves to death as a part of a game.

During the choking game, children get a brief high by temporarily strangling themselves and cutting off the supply of oxygen to their brain.

The game can have deadly consequences, though, if the child can't take off the rope or cord used for strangulation.

Jesse Grant, a 12-year-old Ontario boy, thought he was just playing a game when he put the computer cord around his neck.

"He promised me he wouldn't play it again," Sharron Grant, his mother, said. "He said 'I won't do it again'."

But last April she found Jesse dead with the cord around his neck after he played the game alone.

Dr. Mark Chandra, an emergency physician at the Huronia District Hospital in Midland, Ont., warned about the serious effects of the game.

"This is not a game," Chandra said. "It is as dangerous as using drugs, as dangerous as using alcohol and the consequences can be disastrous."

He believes kids are addicted to the temporary high.

"Because it's addictive you're looking for the high now," he said. "Kids can even start to do it alone."

About four deaths have been linked to the choking game in recent months. Doctors suspect more children have died from the game, but their deaths were wrongly classified as suicides.

One such case was the death of a nine-year-old boy from Alberta two days before Christmas.

"He was on his knees. The belt was around the neck," his mother, who didn't want to be identified, said.

Police said he committed suicide. His mother was unconvinced, though.

"I knew in my heart there's no way that's what this could have been," she said. "He was a happy kid."

Police later called the death accidental after they suspected the boy died from the choking game.

"Certainly, I've treated other kids who died from what we thought was suicide. Who knows, could it have been part of this tragic game they've been playing?" Chandra said.

Grant has created a website, www.deadlygameschildrenplay.com,  to educate people about this dangerous game.

"I want parents, teachers and children to know it's deadly," she said.

From the website, signs a child is playing the choking game:

• Any suspicious mark on the side of the neck, sometimes hidden by means of a turtleneck, a scarf or a permanently turned-up collar
• Changes in personality, such as overly aggressive or agitated
• Any kind of strap, a rope or a belt lying about near the child without any reason – questions about such objects are often eluded
• Headaches, sometimes excruciatingly bad ones, loss of concentration, a flushed face
• A thud in the bedroom or against a wall – meaning a fall in cases of solitary practices
• Any questions about the effects, sensations or dangers of strangulation
• Other names for the game: Blackout, Fainting Game, Space Monkey, Dream Game, Suffocation Roulette, Pass-out Game, Flat liner, California Choke, Space Cowboy, Airplaning and many more.

"After he died, we realized those signs were there," Grant said in an interview with CTV's Canada AM on Friday.

"Had I known that information back then, I could have sat him down and said, 'Look it, 150 children here, look at these children who have died between 9 and 14.

"And you can't be doing this."

With files from CTV's Avis Favaro