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Troubled actor Nick Stahl has gone missing again after checking out of rehab against his doctor's advice.

The "Terminator 3: Rise Of The Machines" star first disappeared for more than a week last month but he re-emerged and was admitted to a rehab clinic.

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Stahl, who has battled a drug problem, walked out of the California center earlier this month and went to stay at a pal's house.

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However, his family and friends are once again searching for Stahl after he failed to return to his friend's home. He was last spotted on Thursday.

A source tells EOnline.com, "Now he's disappeared. We can't find him anywhere. He has not made contact with anyone. We are all just desperately looking for him."

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"Everyone just wants him to come home. It's a terrible situation. We are searching, but we've had no solid leads."