Brawl at Waka Flocka Charity Event

According to sources, the fight was over money -- the guy who throws the first punch is one of Waka's former proteges. He accused Waka of owing him cash.

Waka's rep tells TMZ, the rapper was trying to do a good thing for his community and got ambushed. Although Waka chases the guy down and his posse beats the dude up, Waka's rep says he was just defending himself.