A blue whale near Sri Lankan town of Mirissa on January 21, 2012. A possible reason for the name "Blue Whale Challenge" is that the creators likened beached blue whales to suicide. S.KODIKARA/AFP/Getty Images

The family of a San Antonio, Texas teen who killed himself Saturday claimed the 15-year-old’s suicide was the latest in a string of suicides resulting from the internet death group phenomenon called the “Blue Whale Challenge,” ABC-affiliate KSAT reported Monday.

Isaiah Gonzalez’s family found him hanging in a bedroom closet Saturday morning. A cellphone was placed on top of a shoe, indicating he broadcast his suicide on social media. His family said they believe Gonzalez killed himself as part of a suicide obstacle course known as the “Blue Whale Challenge.”

Read: What Is ‘Blue Whale’ Suicide Challenge? Teen Girl Throws Herself In River For Russian 'Game'

“We had no signs at all. Isaiah was Isaiah,” Isaiah’s father, Jorge Gonzalez said to KSAT. His mother described him as a happy teen who just joined ROTC and was set to begin his sophomore year of high school, according to NBC-affiliate WOAI.

The Blue Whale Challenge was identified as an online “obstacle course” consisting of 50 daily tasks ultimately culminating in the participant’s suicide. The name of the challenge derived from beached whales, an occurrence the creators of the challenge allegedly likened to suicide. It is believed to have originated in Russia, with multiple suspected coordinators targeting children and teenagers on the VKontakte social network. Two possible creators of the challenge were arrested in June.

Ilya Sidorov, 26, confessed to creating the game after he reportedly told a 13-year-old girl in a Russian village to jump under a train. He was in correspondence with 32 more teenage girls. Philipp Budeikin, 21, was also held by Russian police for attempting to make 16 girls commit suicide. Budeikin said to Russian press that he was “cleansing society” with the challenge.

The challenges ranged from participants waking up early to watch a scary movie to participants carving a whale into their arm. Participants are instructed to post photos and videos of themselves completing the challenges online. Isaiah Gonzales’s family said he sent his friends photos of him completing the tasks.

In order to participate in the “game,” online users posted on social media asking for a “curator,” according to the Washington Post. The curator is tasked with providing the 50 daily challenges. The curator and participant are instructed to be in constant contact in those 50 days.

The number of teen suicides that resulted from the challenge is unknown, but related suicide cases involving electronic devices, social media and similar tasks have been reported around the world.

Read: Blue Whale Challenge: Authorities Warn Parents, Teens About App That Encourages Self-Harm, Suicide

Several cases appeared in the United States as well. A family in Atlanta reported their 16-year-old daughter’s suicide which occurred under similar circumstances, reported CBS-affiliate WNCN Monday. The Baldwin County Public School System in Alabama also warned parents about the challenge in May.

Prior to his son’s death, Jorge Gonzalez asked his children about the “Blue Whale Challenge.” Isaiah told his father he knew of it, but would not participate. Gonzalez addressed other parents about the game:

“I want them to go through their phones, look at their social media,” he said, referring to parents checking their children’s online presence. “If they’re on that challenge already, they can catch that from happening.”

The family set up a GoFundMe page to raise money for funeral costs.