BUENOS AIRES, Argentina -- Justin Bieber is blaming food poisoning for forcing him to quit the stage for the second time during his South America tour. This time he drew boos from a huge crowd in Buenos Aires' River Plate stadium who paid up to $320 to see their idol perform up close.

"I'm not feeling too good, I think I'm out of energy," he told the crowd, saying he was sorry and blowing a kiss before walking off the stage with his head hung low.

Bieber posted a "selfie" photo on Twitter showing himself receiving intravenous fluids, and his manager Scooter Braun came to his defence Monday with a statement laying out a version of Bieber's wild weekend.

Braun said Bieber's food poisoning was so severe that he spent eight hours on an IV drip before Sunday night's show, and doctors advised cancelling, but that the young star didn't want to disappoint his fans.

The concert began at 4:30 p.m., but all the warm-up acts had come and gone by the time Bieber finally felt well enough to go onstage after 10 p.m., an hour and a half later than scheduled. He then performed for "nearly an hour" before he had to give up, Braun said.

Braun also tweeted a message saying his charge "had a rough night but handled it like a man who cares and put his beliebers before himself. very proud. he will be back!"

Neither statement from the manager made mention of the trail of troubles Bieber's tour has left in its wake, and Braun did not immediately respond to a detailed request for comment about them.

The 19-year-old star also walked off the stage in Brazil, ending a concert early after someone threw a plastic bottle at him, an unverified photo circulated on the Internet purportedly showing him crashed in bed and Brazilian police tried unsuccessfully to question him about defacing a public building with graffiti, a crime that carries a year's prison sentence.

In Argentina, wild girls caused such a ruckus outside the Faena hotel that Bieber had to leave. He then flew to Cordoba for a Friday night concert, and still had enough energy to take his entourage to a Buenos Aires nightclub early Saturday morning.

A paparazzi videotape shows Bieber's bodyguards leaving the Ink club after daybreak Saturday, hustling someone out under a black sheet into one of two vans loaded with young girls. The bodyguards can then be seen chasing down and assaulting the nightclub's house photographer, Diego Pesoa, and damaging his camera.

According to an account he gave the website ciudad.com.ar, the photographer's lawyer, Matias Morla, accused Bieber of approving the assault, and said his bodyguards also illegally entered the club's security area to review videotapes of the incident. He said he obtained a court order barring the guards from leaving the country.

After police tried to question the bodyguards at the second hotel, the entourage relocated yet again, to a private property inside a gated community north of the capital, reported Telam, Argentina's state news service.

Morla did not immediately respond to requests for comment, but federal police confirmed that Pesoa's formal assault complaint is being investigated by federal prosecutor Dora Olivieri. A request for comment left by The Associated Press with her office also was not immediately returned.

Bieber's next concert was scheduled for Tuesday night in Santiago.