Robert Downey Jr.'s Son Indio Arrested for Cocaine Possession: Police The actor speaks out about his son and thanks police for "their intervention."

 -- Indio Downey, son of "Avengers" actor Robert Downey Jr., was arrested for possession of cocaine and drug paraphernalia in West Hollywood, the Los Angeles Sheriff's Department said today.

Downey, 20, was arrested Sunday afternoon after police perceived narcotics activity in the car the actor's son was a passenger in off Santa Monica Blvd., authorities said.

“He was smoking something and it wasn’t a cigarette,” a police official told ABC News.

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Downey was released Sunday night around 9 p.m. on $10,000 bail, authorities said.

Indio Downey is the son of the actor and singer Deborah Falconer.

Downey Jr., 49, himself has had notable run-ins with the law, including court-ordered rehab in 2002.

Downey Jr. sent a statement to ABC News, saying, "Unfortunately there's a genetic component to addiction and Indio has likely inherited it. Also, there is a lot of family support and understanding, and we’re all determined to rally behind him and help him become the man he's capable of being. We’re grateful to the Sheriff’s department for their intervention, and believe Indio can be another recovery success story instead of a cautionary tale.”