Blue Whale Challenge
The first to report on this was the Russian newspaper Novaya Gazeta, in 2016. It  linked many suicides of children. All these children had been members of the group "F57", in the Russian social network called VK. The article claimed there were 130 suicides because of the challenge. The article was later criticized, because it made connections where none existed. None of the suicides were found to be related to the activities of the group. There were several suicides which have been linked to the challenge. So far, no link has been proven.