This weekend, adult film star Brian Pumper was caught on camera, beating up a man at the Hollywood train station in Los Angeles.

A passerby spotted Brian squaring up against another man, a much smaller Caucasian guy. In the video, you see Brian move towards his opponent aggressively - then he starts swinging.

Brian's opponent immediately goes into a defensive crouch and eats all the punches that Brian throws at him.

Unfortunately the train pulled off, before we could see how the fight ended.

Here's the video:

Brian has not spoken publicly on what caused the fight.

Brian began performing in adult films in 2001. In 2004 he won the AVN Award for Best Three-Way S*x Scene, He won another AVN in 2007 for "Best Hardcore An*l", and another in 2009 he won for "Best Interracial Or*l".

Brian was eventually black-balled by the adult industry in 2009, after he allegedly forged an STD test for a female performer

He has appeared in over 950 titles since 2001. In July 2010 it was announced that he will star in a film with Montana Fishburne, the daughter of actor Laurence Fishburne. This film was subsequently released as "Phattys Rhymes and Dimes 14", with Montana appearing under the name "Chippy D". In 2011 Pumper began to pursue his rap career releasing songs such as "Porno Ni**a", "Oh And It's Shaved", "Swingin Da Lead", "Swiftly" and "Pumper"