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Singer Adam Levine thrilled fans at a bar in Los Angeles when he belted out his classic Maroon 5 hits - in disguise.

The frontman recently visited Hollywood hotspot Gaslite wearing a fake beard, a prosthetic nose, a flannel shirt and a hat to sing karaoke.

The unsuspecting crowd failed to realize the talented man on stage was Levine - until he starting singing hit track "She Will Be Loved."

A source tells America's Star magazine, "First he sang two songs in the disguise. Then he came out as himself, and the crowd went crazy! No one had any idea it was him until he started belting out Maroon 5 songs."