New York (CNN) Colin Kroll, co-founder and CEO of the hit gaming app HQ Trivia, was found dead Sunday morning in New York. He was 34 years old.

"We learned today of the passing of our friend and founder, Colin Kroll, and it's with deep sadness that we say goodbye," a spokesperson for HQ said in an emailed statement. "Our thoughts go out to his family, friends and loved ones during this incredibly difficult time."

Police found Kroll in the bedroom of his New York apartment, after Kroll's girlfriend called the New York Police Department asking for a wellness check, a law enforcement source told CNN.

Police are investigating Kroll's death as an apparent drug overdose, because a white substance in an envelope was found next to Kroll when he was discovered by police, the law enforcement official said.

Kroll was unconscious and unresponsive and pronounced dead on the scene. Police notified his family, according to New York Police Detective Ahmed Nasser. The Medical Examiner will determine the cause of death.

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