Kevin Mazur, WireImage
Bieber, who is known to love a good live show surprise, staged an impromptu performance at Selena's California gig. The star walked out onstage, mic in hand, and serenaded Selena, much to her and her unexpected fans' delight.
Bieber gave Gomez a big hug before launching into a musical medley, including his track 'Favorite Girl.'
After the show, Bieber took to to his Twitter page to thank Selena's fans for their warm reaction to his concert crashing. "had a #greatnight and surprised the people. felt good to be on stage," he wrote. Justin also sent a public Twitter message to Gomez telling her, "@selenagomez U did great tonight. Proud of u."
Well when it comes to adorable Bieber/Gomez moments, this one is right up there with the Billboard Music Awards smooch, public "I love you"s while shopping together and the most recent episode of PDA, their karaoke duet.
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