Joe Jonas has sparked speculation that he is dating country songstress Taylor Swift after the 19-year-old Jonas Brother was spied secretly attending her concert in West Palm Beach on Sunday night.

According to eyewitnesses, Joe arrived at the Rascal Flatts concert at Cruzan Amphitheatre five minutes before Taylor, 18, took the stage.

“I spotted Joe quickly, but he was trying to hide from the crowds by tucking in-between a few people,” says Mishelle Rivera, Assistant Promotions Director for Miami’s Y-100 Radio. “He was wearing a baseball cap and real casual dress so he wouldn’t stand out.”

“He watched only her performance, then walked backstage to the meet and greet area. But when he saw people start to recognize him, he hid. It was real obvious he didn’t want people to know he was there to see Taylor.”

A rep for Swift insists that the pair are just friends. “They are friends and she’s friends with all the Jonas Brothers.”