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The Belieber (as Justin's fans are known), 14-year-old Amilia Radevska, saw a hole in the beefed-up security team, and decided to make a break for it. As Brian stepped in and restrained the wayward teen, she apparently kicked and screamed "stop it Brian".

"I was looking around and saw a crack in security and thought 'Now or never," Radevska said. "He told me he loved me and it was all ok before I was dragged away."

The attempted mobbing went down as AGT host Grant Denyer interviewed Justin after his performance, during which the pop star sang a six-minute medley of his biggest hits.

About 800 tickets to the show were given away via radio competitions, with around 1,000 fans actually showing up to wait outside the Docklands studios in Melbourne, trying to catch a glimpse of the Canadian-born singer.

In comparison to Justin's 2010 promotional trip to Australia, things have been relatively calm so far. Justin has been spotted repeatedly signing autographs and posing for photos with fans outside his hotel (the location of which was leaked via Twitter). He has also managed to enjoy a meal out with girlfriend Selena Gomez, who has joined him on the whirlwind promotional trip.

During Justin's 2010 visit to Sydney, his planned Sunrise concert at Circular Quay was shut down by police due to unsafe conditions, leaving 5,000 Beliebers to storm the Sunrise studios in Martin Place. The singer was snuck into the Sunrise studios to perform one song, driving the fans crazy.

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