Selena Gomez fans chase Justin Bieber at concert

Justin Bieber and Selena Gomez attend The 2011 ESPY Awards on July 13, 2011, in Los Angeles

(CBS) Justin Bieber made a surprise visit to girlfriend Selena Gomez's concert on Saturday night, but had to make a hasty exit after nearly being mobbed by fans.

After word got out that Bieber was there, dozens of fans reportedly chased him as he tried to leave the venue through a back door.

Pictures: Justin Bieber

Britain's Daily Mail reports that the 17-year-old heartthrob barely managed to make it to his car before the fans descended. Witnesses told the paper that the fans were so frenzied, they feared a riot almost happened.

Earlier in the day, according to the paper, Bieber tried to throw his fans off track by mentioning on Twitter that he was in Canada. The message no longer appears on his Twitter page.

Before he was spotted, Bieber had reportedly been watching the show from backstage with his friend, fellow singer Sean Kingston.

The all new
CBS News App for Android® for iPad® for iPhone®
Fully redesigned. Featuring CBSN, 24/7 live news. Get the App