The family of a 16-year-old Georgia girl who committed suicide in early May believe she was involved in the online suicide “game”  known as the “Blue Whale Challenge,” reported CBS-affiliate WNCN last week.

The girl, identified only as Nadia to protect her family’s privacy, was an artist whose last pieces of art consisted of drawings and paintings of blue whales. After she took her own life, her older brother, Marty, began searching for warning signs. He discovered several clues that linked his sister to the online suicide obstacle course called the “Blue Whale Challenge.”

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Her sketchbook contained whale drawings, magazine cutouts with the phrase “I Am a Blue Whale” on top of them and drawings showing self-harm accompanied with suicidal thoughts.

“None of us knew about this Blue Whale game,” Marty said. “I spend a lot of time online and hadn’t come across it until it happened.”

The “Blue Whale Challenge” is defined as an online “obstacle course” made up of 50 daily tasks that ultimately culminate in the participant’s suicide. The name “Blue Whale Challenge” was derived from beached whales, a phenomenon the game’s creators allegedly likened to suicide. The challenge is suspected to have originated in Russia, with multiple suspected creators. The creators specifically targeted children and teenagers on the VKontakte social network.

Nadia’s family discovered letters in Russian among her journal and her artwork. Some seemed to be love letters, while others appeared to show signs of correspondence with someone. Her family was confused because she never showed interest in learning Russian.

Challenges ranged from participants waking up at 4:20 a.m. to watch a scary movie to participants self-harming. Participants uploaded photos of themselves completing the challenges online. Prior to her death, Nadia posted photos of her legs dangling over her house roof, cuts on her body and train tracks with the word “goodbye.”

“She never had Facebook, never posted pictures. Most of the time, she only wanted to draw,” Nadia’s mother said to CNN. “I never thought she would go and try to find a site or a way to chat with people and believe them.”  

To participate in the game, online users requested a “curator” by posting in different social media forums, according to the Washington Post. The curator is charged with providing the 50 daily challenges. During those 50 days, the curator and the “player” are instructed to be in constant contact.

It is unknown how many lives the “Blue Whale Challenge” claimed, but cases with similar circumstances involving social media and grisly tasks have been reported around the world. Cases appeared in the United States as well. A San Antonio teen who committed suicide in early July 2017 also seemed to be a participant in the challenge.

Nadia’s family reported her suicide to the Georgia Bureau of Investigation, and they opened a Child Fatality Review of her death. Special Agent Trebor Randle said her case is potentially the first “Blue Whale Challenge” case in Georgia.

“Obviously, doing nothing about it has seen a rise,” he said. “Kids know about it and may already be doing it. Parents and educators are the ones who don’t know.”

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Nadia’s family said that looking back, signs of Nadia’s suicidal thoughts were everywhere. She made some of her drawings in class.

“She wrote some of this stuff right in front of her teachers. Right around her friends,” Marty said. “This is a thing that is happening, so people should know, especially parents that have kids that could potentially be subjected to the same thing and also to ask for help.”

Two men were arrested separately in June 2017 under suspicion of being creators of the challenge. Ilya Sidorov, 26, confessed to creating the game after attempting to coerce over 30 girls into committing suicide. Phillip Budeikin, 21, was held by Russian police for attempting to convince 16 girls to commit suicide. Budeikin said he was “cleansing society” with the challenge.