At first it sounds like a freak accident: A soccer net topples, killing a young person on a playing field, a place where kids are supposed to be safe.

But accidents involving soccer goals like the one that killed a 15-year-old girl Wednesday afternoon in Bradford, Ont., north of Toronto have happened before.

The girl was playing on the field with a friend when she became trapped under the crossbar of an overturned soccer net, according to South Simcoe police. Friends and teachers have identifed the girl as Jaime Palm.

Unable to lift the heavy net, her friend called 911. Palm was rushed to hospital, where she died.

Police are investigating what caused the net to tip over but other — almost identical — accidents have prompted a push in some jurisdictions for laws requiring that soccer nets be anchored to the ground or switched out in favour of safer, tip-proof designs.

Soccer nets are often made of metal and can weigh a few hundred pounds, and their design often makes them top heavy and prone to falling forward onto the field of play.

This soccer goal killed a five-year-old girl in Watson Lake, Yukon in 2012. (CBC)

In July 2012, a five-year-old girl died in Watson Lake, Yukon, when a soccer net tipped over on her as her parents stood nearby.

A CBC.ca story about the Watson Lake accident quoted Toronto-based neurosurgeon Dr. Charles Tator, founder of Think First Canada, a brain and spinal cord prevention agency.

"It's been recognized for a long period of time that goal posts that are improperly anchored can cause injury, and in fact there are several recorded fatalities from falling goal posts," he said.

A coroner's report into the Watson Lake death found that the net was in poor condition at the time of the accident.

In Montreal 2001, a 14-year-old boy was killed after an unsecured soccer net fell on him causing a fatal head wound. The Quebec coroner’s inquest recommended all park soccer nets be anchored to the ground.

6-year-old's death prompted soccer net law

In October 2003, six-year-old Zachary Tran died when a goal fell on him during soccer practice in the north Chicago suburb of Vernon Hills, Ill. The 180-pound net tipped forward, striking Zachary on the back of the head. He died of cardiac arrest caused by massive head injuries.

Six-year-old Zachary Tran died in 2003 when a soccer net fell on him during a practice. His death prompted his parents to raise awareness about the dangers posed by unsecured soccer nets. (Tran Family)

Tran's parents made it their mission to raise awareness about the dangers of soccer goals and to prevent similar deaths. They pushed for an Illinois law — which passed in 2011 is named after their son — that bans the manufacture or sale of new movable soccer goals that are not tip-resistant. Older goals in Illinois must be properly anchored to the field and schools and soccer organizations in the state are required to have safety plans for movable goals.

Zachary's parents also started a website called Anchored for Safety, which chronicles soccer-net deaths. According to statistics compiled on their website, soccer nets have caused 38 deaths since 1979. Each incident is listed here.

Through the website, the family argues that in the short term, all soccer goals should be secured to the ground so they can't tip over. A long-term goal is to promote tip-proof designs for soccer nets.

The Tran family says other jurisdictions, including Canada, have not passed similar legislation, and that thousands of unsafe soccer goals remain in use across North America.

A YouTube video, posted on the channel of the family's law firm, tells Zachary's story.

In the video, Zachary's mother Michelle Tran said that when her son's accident happened, she was shocked to learn that his death was the 27th time someone in the U.S. was killed by a soccer goal that tips over.

"We didn't know that these structures were unsafe," she said.

Zachary's father Jayson Tran said parents should be on the lookout for any soccer goal that is not anchored to the ground.

"Keep your children away from it or make sure that it is properly secured," he says on the video.

"We want parents to know that an unanchored soccer goal is ... dangerous. When parents see a soccer goal … they need to check it. To make sure that goals are properly anchored. Parents need to report an unanchored goal to whoever owns that goal."