Facepalm: Not for the first time, a social media platform has been forced to warn users not to take part in a challenge that could seriously injure or even kill them. TikTok, the popular app that lets people create 15-second video clips, has said it would remove any content that encourages or replicated the skull-breaker challenge.

The prank, which has mainly been carried out by teens, involves two people tricking someone into standing side-by-side with them before jumping into the air, at which point the victim has their legs kicked away and they crash to the floor, hence the skull-breaker name.

The challenge has already resulted in two 13-year-olds putting a classmate in a hospital with a head injury and concussion that caused a seizure. The two seventh-graders have been charged with aggravated assault and third-degree endangering an injured victim. A girl in the UK was also hospitalized after the stunt left her with severe spinal injuries.

In an updated post, TikTok wrote: "The safety of users is our top priority at TikTok, and we do not allow content that encourages or replicates dangerous challenges that might lead to injury. In fact, it's a violation of our Community Guidelines and we will continue to remove this type of content from our platform. More importantly, we encourage everyone to exercise caution in their behavior whether online or off. Nobody wants their friends or family to get hurt filming a video or trying a stunt. It's not funny - and since we remove that sort of content, it certainly won't make you TikTok famous." The company is also encouraging users to report videos showing the skull-breaker challenge.

Dangerous and stupid viral challenges are nothing new of course. You might remember the Tide Pod challenge that saw YouTubers biting into or swallowing the detergent-filled pods, which are potentially toxic. There was also the Kiki challenge that involved dancing to Drake's "In my feelings" next to a slowly moving car, resulting in several injuries.