Malcolm-Jamal Warner's cause of death has been released by police. The actor, who is best known for his role as Theo Huxtable in the hit TV sitcom "The Cosby Show," died on Sunday off the coast of Costa Rica after a drowning, Costa Rican National Police told ABC News. He was 54.

Warner’s follow-up to Jeremiah saw him heading back to sitcom territory, this time as a sidekick to none other than former Seinfeld cast member Jason Alexander. Listen Up was the George Costanza actor’s second attempt to lead his own comedy after the hit NBC series ended, and starred him as sports commentator and family man, Tony Kleinman.

The beloved actor died at 54 while on vacation with his family in Costa Rica. Learn more about his sudden passing and cause of death here.