Jan 2, 2009, 9:30 GMT
Joaquin Phoenix has sparked fears for his health after he was seen behaving erratically at a Miami nightclub.
11/01/2008 - Joaquin Phoenix - The 'Walk the Line' star - who recently announced he is quitting acting in order to pursue a music career - was at LIV nightclub earlier this week when he leapt on stage while Jamie Foxx performed and started to "grind" against him. © Chris Hatcher / PR Photos
The 'Walk the Line' star - who recently announced he is quitting acting in order to pursue a music career - was at LIV nightclub earlier this week when he leapt on stage while Jamie Foxx performed and started to "grind" against him.
An onlooker told the New York Post newspaper: "Joaquin jumped onstage as Jamie was singing 'Gold Digger' and started dancing. He even took a barrette out of some girl's hair and put it in his hair.
"Jamie started singing a song from his new album and Joaquin danced with him. It looked like they were grinding."
Joaquin, 34, shocked fellow partygoers with his dishevelled, bloated appearance, sporting a bushy beard and long, matted hair.
The actor has previously completed a stint in rehab for alcohol addiction, and his friends are reportedly becoming increasingly concerned about his strange behaviour.
One said: "For people who know Joaquin, it's been an incredibly traumatic year, filled with chaos. Everyone wants to help but nobody's been able to break through. His bizarre behaviour has everyone worried. It's just getting scary."
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