50 Cent Pounds Co-Star

Rapper Curtis "50 Cent" Jackson appears to be as much of a gangster on camera as he is off - and actor Frank John Hughes found that out first hand. We learned that the two got into a physical confrontation on the set of their new movie Righteous Kill.

According to a person who witnessed the incident, 50 Cent and Frank Hughes (photo'd below) got into a heated argument when the actor confronted 50 about not knowing his lines. And the argument reportedly turned physical. "Frank tried to correct [50 Cent] and he got really upset ... Before it was all over [50 Cent] had Frank on the ground pummeling him."

And while Frank appears to have survived the mauling, the rest of the cast and crew haven't. Our insider continued, "The paramedics looked at Frank and he's OK. It's everyone else here that's still shaken up .... No one is trying to get on [50 Cent's] bad side."

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