Um, WHAT?!

Zac Efron and his bodyguard got into an altercation with a group of homeless people around midnight on Sunday near the Skid Row area of Los Angeles, according to TMZ.

Zac told authorities that he and his bodyguard had run out of gas and were sitting in their car, and while waiting on a tow truck they threw a bottle out of the window. It's not clear what was in the bottle, but when it broke on the pavement near a group of transients, chaos broke out. Zac said the transients confronted him and his bodyguard, and two of the individuals then attacked the bodyguard. When Zac got out of the car to help, he got socked in the mouth and told cops, "It was the hardest I've ever been hit in my life."

Cops were on patrol under the Harbor Freeway when they saw the fight, but no one was arrested because they viewed it as "mutual combat." One source tells the website that Zac was "obviously intoxicated." Seeing as he was in rehab twice last year for cocaine abuse, this isn't exactly a good thing! Skid Row is a notoriously bad neighborhood and police are frequently on high alert there for drug deals and gangs ... it's certainly no place for the former High School Musical hottie!