Sydney police shut down a concert by teen singing sensation Justin Bieber amid safety fears after young fans were injured in crowd surges before the free event.
Thousands of fans had gathered in the Rocks area of the city - many camping overnight - ahead of 16-year-old Bieber's three-song show at the Overseas Passenger Terminal.
But officers called the concert off when some in the crowd began pushing, crushing and trampling others in the audience.
Several young girls were injured, carried off on stretchers, and police brought in extra teams to disperse the crowd.
"Police at the event were concerned for the 4,000 excited people already in attendance with many more anticipated to arrive prior to the start of the performance," New South Wales police said.
Monica Caruana, 14, who arrived for the concert at 12.30am with her four friends, said it was absolute mayhem.
Free concert crush 'scary'
One of the girls in their group was "knocked out" in the crush.
"The doors were meant to open at 5(am) but they opened at 3(am) for some reason and everyone bolted," she told AAP.
"It was really scary, really badly organised.
Thirteen-year-old Jessica Whatmore said she was terrified of being trampled.
"I couldn't wait to get out of there," she said. "Girls were pushing and shoving and I thought I was going to get hurt."
Sonia Agresta, who flew from Melbourne with her 14-year-old daughter Therese for the concert, said the scenes were chaotic.
"Very disappointing for the kids," she said of the cancellation."But safety was an issue... it was crazy.
YouTube, Twitter sensation
"It was a really hard call, but I'm not the only one that has flown, some came from Brisbane, Perth. We've all come for the same thing - to see him perform."
Baby-faced Bieber, who rose to fame after his mother posted clips of him singing on video-sharing website YouTube, later apologised for the cancellation.
"I am so sorry that it got out of control... we don't want anyone to get hurt," Bieber told concert organisers Channel Seven. "It gets crazy sometimes."
Earlier the teenager had vowed the show would go on, telling fans on mico-blogging website Twitter: "I don't cancel".
"I love my fans...I love it here in Australia...and I want to sing."
He later performed just one song on Channel Seven's Sunrise breakfast show - from behind plate glass windows.
