FILE - In this Sept. 30, 2012 file photo, Justin Bieber performs at the MGM Grand Garden Arena in Las Vegas. Bieber is recovering after fainting backstage at a concert in London on Thursday, March 7, 2013. A spokeswoman for Bieber said that the 19-year-old pop star was given oxygen and took a 20-minute reprieve after fainting backstage at his show at London's O2 Arena. (Photo by Isaac Brekken/Invision/AP, File)
(AP) -- Justin Bieber is recovering after fainting backstage at a concert in London.
A spokeswoman for Bieber said late Thursday that the 19-year-old pop star was given oxygen and took a 20-minute reprieve after fainting backstage at London's O2 Arena.
Bieber posted a shirtless photo of himself in a hospital bed late Thursday with the caption: "Gettin better listening to Janis Joplin." Before that on Twitter he thanked "everyone pulling me thru tonight."
"Best fans in the world," he wrote. "Figuring out what happened. Thanks for the love."
Jazz Chappell, a 20-year-old concertgoer who brought her younger sister and her friend to the show, said Bieber announced he couldn't breathe and needed water. He resumed performing, but then had to be helped offstage by a backup dancer. In the nearly 30 minutes he was offstage, some fans started to leave. Once his manager announced what had happened, Chappell said many fans in the audience were gasping and crying, while others kept cheering for him to return.
"I thought, 'Give the guy a break. He just fainted. He's not a performing horse. Let him rest a second,'" said Chappell.
In a video of the concert posted online, Bieber's manager, Scooter Braun, appeared onstage and told the crowd that the singer was feeling "very low of breath" but would come back to finish the show.
In another video posted online that claims it is from Thursday's show, Bieber appears out of breath during a performance of his uptempo hit, "Beauty and a Beat." He begins to fade as he is dancing and puts his hand on his forehead and bends over to catch his breath.
Chappell said Bieber, who's in London to perform four concerts at the O2, later returned and performed low-energy renditions of his hits "Boyfriend" and "Baby."
Braun later tweeted "everyone please give him a little space and he will be ok. Im sure he appreciates the support ... Tough kid proud night once again he always finishes the show. Full out. True pro..."
The incident caps a difficult week for Bieber. He was forced to apologize to outraged fans who accused him of taking the stage almost two hours late for his first concert at the O2 on Monday. He insisted he was only 40 minutes late and blamed "technical issues." He took to Twitter to vent his frustrations with the media's portrayal of the incident.
Bieber's Friday night concert at the O2 remained scheduled as of early Friday morning.
AP writers Cassandra Vinograd in London and Derrik J. Lang in Los Angeles contributed to this report.
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