Actor Dimitri Diatchenko has died at 52, according to his agent Roger Paul. His portrayal of Uri in Oren Peli’s 2012 film Chernobyl Diaries garnered mass praise.

The actor died suddenly on April 21 in his home in Daytona Beach, FL, with co-workers notifying the police after being unable to contact him for days. Autopsy results are currently pending, but Diatchenko’s agent said Diatchenko’s death appeared to be either a heart attack or related to an electric shock on a job the week prior.

Diatchenko was a native of San Francisco and a first-generation American of Ukrainian, Greek and Swedish descent. His first major screen appearance was a small role as a Navy SEAL in Ridley Scott’s 1997 G.I. Jane starring Demi Moore. Since then, he landed numerous recurring roles and starred as a guest on shows like How I Met Your Mother, Bones, Sons of Anarchy, 2 Broke Girls and Criminal Minds. His voice was also featured in animated shows like Teenage Mutant Ninja Turtles, Family Guy and The Wild Thornberries. He was also known for portraying Russian characters in such films like Get Smart, Indiana Jones and the Kingdom of the Crystal Skull and Chernobyl Diaries.