Justin BieberJustin Bieber can no longer perform at concert venues without seats for fear of fans being seriously injured.

Rabid Bieber fans have forced the 'Never Say Never' singer's management to put their foot down and refuse to book the star at any arenas or other venues with standing-room only space.

Bieber's bodyguard, Kenneth Hamilton, recently told Rolling Stone that he fears for some of the young fans' safety, saying "You've got a mob pushing, and even if it's little girls, they're crawling on top of each other with their arms and elbows, and getting injured."

Safety and security issues regarding fans' 'fever' for Bieber have been an issue for quite some time. Last April, a Bieber concert in Sydney was cancelled after fans broke down a crowd barrier and stampeded forward, crushing young fans against the stage.