It's war!

Justin Bieber and D-lister Drake Bell have been in a longstanding feud due to the Disney star's incessant insults directed at the singer on Twitter, and The Biebs decided to get back at his enemy last night by crashing Bell's album release party at The Grove!

In an attempt to show the Drake & Josh star how big of a has-been he is, JB did a drive-by and made all the fans go crazy over him, rather than the guest of honor!

We personally think this is hilarious! The few Bell-iebers just turned into Beliebers!