Justin Bieber & Selena Gomez Hang Out at Phish Concert

Who knew they were such big Phish fans?

Pop stars Justin Bieber and Selena Gomez hung out with Phish at their Long Beach Arena show last night south of L.A. According to The Hollywood Reporter, the Biebs was brought to the concert by his musical director, who's apparently a huge Phish groupie!

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They rocked out to the first long set and then went backstage to meet the band during intermission! Justin got introduced to Phish bassist Mike Gordon, guitarist and frontman Trey Anastasio, and dished about music.

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There's actually a Phish connection to the Canadian's next tour: Their lighting director, Chris Kuroda, will be responsible for the design!

No stranger to photos, they posed backstage with the band members' extended family. As for the second set, Justin and Selena got into the spirit of things and hurled glowsticks!

In case you're not familiar, glowstick wars break out at every Phish show. This particular concert had a war during the first two songs and according to an insider, "They were having a blast."