The family of a 16-year old girl who committed suicide in May uncovered clues that connect it to an online "challenge" called "Blue Whale," where participants are given different tasks, the last of which is to die by suicide.

After her death, the teen's older brother started going through her things to search for signs that they may have missed. His search led him to a sketch of a girl with a name written in Russian. Looking it up online, he found that the girl was 17-year old Rina Palenkova, and the sketch his sister had made was of Palenkova's last photo which she posted online moments before she committed suicide in Russia in 2015.

The teen, who was a talented artist, spent most of her time painting and creating sketches. The family also found pages of whale drawings with magazine cutouts spelling out the phrase "I am a blue whale" pasted over them. They also found drawings indicating self-harm, suicidal statements of farewell, and several entries in Russian.

"None of us knew about the Blue Whale game," the brother told CNN. "I spend a lot of time online and hadn't come across it until it happened." He added, "If I had come across the Blue Whale game online or heard about it from somewhere, maybe I could have pieced it together a little bit faster."

While this might be the first suicide case in United States to be linked to "Blue Whale," a second case reported in July, where a 15-year old boy from Texas took his own life, is also said to be connected to it, according to a report from The Washington Post.

The attention given to Palenkova's death led to the discovery of something called "Blue Whale," a challenge that incites suicide among teens. It reportedly began on Russia's social networking site, VK.com. Since Palenkova's death in 2015, multiple cases of suicide in parts of central Asia, Europe and South America have been linked to "Blue Whale."

The "challenge" is said to be administered by an online curator who provides daily tasks over 50 days. Participants are required to send photographic evidence after completing each task. At the end of the "challenge," the participant is pushed to commit suicide.

The name "blue whale" comes from the phenomenon wherein the animals intentionally leave themselves stranded on beaches.

According to 2015 statistics from U.S. Centers for Disease Control and Prevention, suicide is the third leading cause of death among persons aged 10-14, the second among persons aged 15-34 years.