Justin Bieber attacked outside Macy’s In New York (Video).

Mail Online - These pictures show the dramatic scenes as an undercover NYPD cop was allegedly taken out by one of Justin Bieber's own bodyguards.

The undercover policeman was mistaken for a crazed fan trying to attack the teenage superstar in a bizarre melee that resulted in one of Bieber's own security guards being issued with a summons.

The pint-sized singer was at an event at Macy's department store in New York when the cop was allegedly grabbed by a bodyguard as screaming teenage girls surged towards the 17-year-old.

The plain-clothed officer stepped in to protect the Canadian heartthrob from the crowd surge when an overprotective Bieber bodyguard allegedly grabbed him and tried to pull him away from the boy.

Bieber was reportedly shaken up by the incident, which saw the bodyguard issued a summons for disorderly conduct.

Initial reports from the scene had suggested that a man had jumped the barricades, attacking Bieber and knocking him to the ground - but police have since denied that he was touched or hurt.

‘It was a momentary well-intentioned misunderstanding and the event went well,’ a spokesman for Bieber told the New York Post. ‘He’s completely fine and has no injuries.’

A witness said the 17-year-old Canadian singer shouted: 'What? What?' as the incident happened, before rushing back into the store and not talking to waiting reporters.

Dozens of fans had camped out in front of the famous store for two days to get the opportunity to meet their idol, who was doing a personal appearance to launch his new fragrance Someday.

Another witness told the New York Daily News that people who had been waiting for hours got too excited and began pushing the barrier down, meaning he did not even get time to wave at his fans.

Bieber's fans, known as 'Beliebers', rallied to support the singer after the incident, on the initial understanding that somebody had tried to attack him.

One young lady was so overcome by the incident that she had to be carried away by police officers.

Bieber has had other security scares including at an event in 2009 at the Roosevelt Field Mall that was cancelled after thousands of fans mobbed the shopping centre.

He tweeted to his followers to leave the mall because police threatened to arrest out of control fans.