A Justin Bieber fan tackled the singer onstage during a concert in Dubai over the weekend, according to a United Arab Emirates report and a mobile phone video posted on YouTube.
News website The National reported that an unsuspecting Bieber was rushed from behind on Sunday night during his second show at Dubai's Sevens Stadium as part of the Believe world tour.
The teen star enraged fans the previous night, and again on Sunday night, when he turned up two hours late for both concerts in the same city.
A video purporting to be of Sunday's concert shows a male in a white T-shirt and denim shorts run onto the stage and grab a singer, dressed all in black, before security officers swarm onstage and tackle the young man.
The singer was able to free himself and dash to the side of the stage just seconds before a grand piano the star had been playing was tipped over in a tussle between the fan and a bodyguard.
Although the piano was rendered unplayable, Bieber and his eight-piece band managed to finish the song without pause while the attacker was removed from the stage, according to The National.
The website also reported that Bieber returned for an encore and finished the concert with the song Baby.
On Saturday, the Boyfriend singer had been expected to take to the stage at the Sevens Stadium at 8pm (local time), but it was only at around 10pm that concert officials announced the star was "on his way", prompting him to be booed by his young devotees.
Many parents later complained about their children being kept awake until the early hours since Sunday is a school day in the United Arab Emirates city, according to local news service Al Arabiya.
Concert organisers, DoneEvents Amg, posted an apology on their Facebook page for Saturday night's delays, saying: "Recent shows on this tour have started late and so the artist was also later than scheduled in taking to the stage last night.
"We really empathise with the fans and their parents who were affected by the delay and to whom this might have caused some inconvenience. We know that many parents had to look after tired and exhausted children both at the stadium and I am sure this morning, as they try to get them up for school.
"All that said the fans who saw Justin in action loved the incredible show he put on and they left screaming with delight as chants for the superstar echoed around the stadium."
They have not posted since Sunday night's reported attack or delay.
Bieber's late arrival comes after he kept fans waiting for two hours at London's O2 Arena in March as part of his current Believe world tour.
- with WENN