I'm pretty sad right now....there seems to be an ungoing, unpleasant, pattern here with my childhood crushes...first RIver Phoenix, than Jonathan Brandis and now Brad...

TMZ has learned actor Brad Renfro is dead.

The 25-year-old actor was found dead at his Los Angeles home this morning. The cause of death has not been determined, however, Renfro had a history of drug abuse.

Sources tell us Renfro, who had starring roles in "The Client" and "Apt Pupil" had been working valiantly to stay clean, especially since this summer. Renfro had been convicted of several drug offenses, including attempted heroin possession.

Renfro had been filming a movie with Winona Ryder and Billy Bob Thornton. The movie, "The Informers," just wrapped.

Renfro has had a rough time personally since moving from Tennessee to Los Angeles. His parents split, and we're told he did not have real guidance from adults as he tried navigating the treacherous movie industry.

i'm just getting a terrible deja vu...

I was so bummed when I heard about this. So freaking sad. I thought he was really talented and while I was never some huge fan, I always enjoyed his work.

They haven't released the cause of death yet, but most already seem to assume it was drug-related, given his history. Guess we'll find out once the autopsy is performed.

My heart goes out to his girlfriend (who had the misfortune of finding him dead), his family and friends. What a horrible shame.