Jason Derulo Fights Two Guys Who Allegedly Mistake Him for Usher

Jason Derulo has a zero-tolerance policy for being mistaken for another R&B superstar -- so much so, he attacked 2 guys at a Las Vegas hotel for calling him ... Usher. Law enforcement sources tell TMZ... cops were called to the ARIA hotel during the early hours of Tuesday morning after Derulo threw fists with the men. SUBSCRIBE: About TMZ: TMZ has consistently been credited for breaking the biggest stories dominating the entertainment news landscape and changed the way the public gets their news. Regularly referenced by the media, TMZ is one of the most cited entertainment news sources in the world. Subscribe to TMZ on YouTube for breaking celebrity news/ gossip and insight from the newsroom staff, the best clips from TMZ on TV, Raw & Uncut TMZ video (from ) and the latest video from TMZ Sports and TMZ Live! We love Hollywood, we just have a funny way of showing it. Need More TMZ? TMZ Website: LIKE TMZ on Facebook! FOLLOW TMZ on