What you must know about the Blue Whale challenge

Participants have to tackle a series of challenges instructed by admins of private groups in social media for 50 days. It starts with watching a scary movie and escalates to extremes, including self-harm. On the 50th day, the participant is asked to commit suicide after documenting the act in the form of videos/photos.

It has been dubbed a hoax, but disturbing selfharm images have appeared on social media showing cuts carved into the skin in the shape of a Blue Whale.

Image: Twitter