According to TMZ, Bieber drove to Mixology at the Grove in Los Angeles, where Bell was hosting the party, and rolled down his window to greet fans. The crowd reportedly went "bonkers" when they saw him.
"To all the fans i just met at the grove...I love you. #beliebers," he wrote on Twitter before posting a video of the scene on Instagram.
The "Boyfriend" singer later shared a picture of Bell looking down at his car on Instagram and captioned it: "Why is @justinbieber sprinter van getting more attention than my album release party." The singer has removed the photo from his account.
Bell, as usual, also took to Twitter to diss Bieber.
"@justinbieber dude ! Thank you for coming to my party I didn't know you were down stairs sorry they didn't let you in!! Should have hmu!!" he wrote.
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