Justin Bieber was spotted partying until the sun rose in Las Vegas last night and he wasn't alone.<br /><br />For more Hollywood news and gossip:<br />http://www.youtube.com/hollywoodbacks...<br /><br />Subscribe at: <br />http://www.youtube.com/subscription_c...<br /><br />Like us on Facebook:<br />http://www.facebook.com/hollywoodback...<br /><br />Follow us on Twitter:<br />https://twitter.com/#!/HollywoodBstage
