UPDATE 1-Justin Bieber "getting better" after collapsing at London gig

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March 7 (Reuters) - Canadian teen pop star Justin Bieber tweeted that he was "getting better" after collapsing on stage from shortness of breath during a performance in London and being rushed to the hospital on Thursday.

Bieber's spokeswoman, Melissa Victor, told Reuters that the singer had fainted on stage at his concert at London's O2 arena and had been taken backstage where he took a 20 minute break and was given oxygen by doctors.

Bieber, 19, returned to the stage after the break and his representatives said he was OK. Victor said the "Boyfriend" singer ignored doctors orders and returned to the O2 Arena stage to finish the performance.

The singer tweeted to his 35 million Twitter followers following the incident, "thanks for everyone pulling me thru tonight. best fans in the world. figuring out what happened. thanks for the love."

His manager, Scooter Braun, told audiences at the arena after the singer's collapse that Bieber was "very light of breath, the whole show he has been complaining," in amateur videos posted on the Internet.

Bieber had not been suffering from any health issues prior to the show, the spokeswoman added.

Fans quickly began circulating the hashtag "#justintakeabreak" on Twitter after news of his collapse spread on the social network.

This is not the first time Bieber has collapsed on stage during a performance. He previously suffered a concussion during a concert in Paris last June after falling into a glass wall.

Bieber's London leg of his sold out "Believe" world tour hasn't been without its problems.

On Tuesday, the first of his four nights at London's O2 Arena, Bieber angered fans by turning up on stage nearly two hours late, blaming technical issues for his delayed performance.

Media outlets also reported that the singer, who celebrated his 19th birthday in London last week, tried to take 14-year-old Jaden Smith, son of actor Will Smith, to a club, where he was turned away, along with Bieber and his entourage.

Bieber took to Twitter and Instagram to vehemently deny the reports that he tried to take underage Smith to a club, saying instead that he was forced to leave the venue when the club's security guards club behaved aggressively towards his fans who were lined up outside. (Reporting by Piya Sinha-Roy and Eric Kelsey in Los Angeles; Editing by Sandra Maler)