His guitarist and musical director Dan Kanter later tweeted: "It wasn't a prank. Someone ran on stage during Believe and the piano got knocked off its platform. Everyone is fine. No need to worry!"
According to The National, Bieber started his Saturday and Sunday shows two hours late.
Chimed a parent of one of Bieber's fans at the gig, Steve Hoare: "The attacker may have been an adoring fan. But it was probably someone who was annoyed at Justin Bieber being more than two hours late, as he was the night before.
"Both nights are school nights here, so it was not clever and pretty arrogant, particularly when you play a set that is only just over an hour long," he told the BBC.
Thomas Ovesen of Done Events, the music promoter behind the concert, told CNNArabic that the incident was not, as was widely reported, considered an "attack".
"It was just a fan aged between 13 to 14 years old [who] jumped on the stage trying to hug his idol and was stopped before reaching the singer," he said. "He was not in possession of anything and was deemed harmless."
He also scoffed at reports that an audio backing track with vocals continued playing while the fracas ensued.
"The show was one hundred per cent live, and the piano kept on playing after one of the band members jumped and kept on playing," he said. "That's why it looked like the piano kept on playing after it was obstructed by the fan."
'I DIDN'T MEAN TO SCARE HIM'
A young man claiming to be the stage crasher has since apologised to the Biebs.
"When your idol come[s] to your city, you know what I mean, I was gonna, just get a chance to go on the stage and hug him and maybe take a picture," said an anonymous listener who dialled in to Virgin Radio Dubai yesterday.
"I want to say sorry and if Justin can hear me, I didn't mean to scare him. I'm a true Belieber."
Listen to audio of the interview below:
Per E! Online, 18-year-old Abdo Gotni has since reportedly claimed he's the man who made the radio apology, and is "upset" by reports that the Biebs was attacked during the show.
"I wanted to say hi and maybe take a picture. I wanted to hug him," he said, adding that he was "just very excited" during the moment, and hadn't planned to storm the stage.
"They [security guards] dragged me offstage and just told me I needed to go home," he said. "They kicked me out of the concert and told me not to come back. They didn't ask me for my name or my ID."
NOTABLE NUGGETS
And finally ...
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* Nick Cannon blames American Idol producers for "perpetuating" Mariah Carey-Nicki Minaj feud; sources say Carey is thinking of bailing on the show.
* Winona Ryder was told she wasn't pretty enough to be an actress.
* Tom Cruise is doing Mission: Impossible 5.
* Snapped: Natalie Portman is all smiles with son Aleph.
* Kim Kardashian posts pic of puffy pregnancy feet. Fill your boots here, foot fetishists.
* Anne Hathaway goes platinum blonde.
* Lindsay Lohan on strict lockdown during rehab stint. That means no blogging, too.
* Caption this: Elton John's hubby David Furnish cops a sneaky feel of Neil Patrick Harris' bum.
* Chris Brown's private jet makes emergency landing.
* Girls Gone Wild creator Joe Francis convicted of assault, false imprisonment.
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