Justin Bieber

Justin Bieber may have passed out on a concert stage in London.

The pop singer struggled and was very short of breath during a show on Thursday night (03.07.13) and the American star collapsed on stage at London's O2 Arena.

Justin - who angered fans when he was two hours late for his show earlier this week - informed the crowd he wasn't feeling well and got checked out by a doctor before returning 10 minutes later to finish his set.

Following the concert, Justin's team immediately brought him to a local hospital for a full check-up.

His representative told E! News: ''He got oxygen from emergency personnel. He insisted on finishing the show. He is on the way to the hospital right now.''

Video footage from the concert also shows Justin's manager Scooter Braun telling his fans that the 19-year-old singer had been ''very low of breath'' during the show and was being checked over by a medical team.

Justin was recently reprimanded by his record company and warned to curb his partying ways and ''stay in more''.

A source said: ''Being amidst a barrage of abuse is uncharted territory for Justin. Understandably he is finding it hard to take ... His antics are not what his young fans expect of him.

''After an emergency meeting in the US, Justin's people had him on Skype to bosses and he was given a serious talking-to.

''It was suggested he start staying in more and basically cleaning up his act ... Justin took the news well and has promised to go back to putting his fans first.''

© Bang Showbiz