Justin Bieber fainted during a concert at London's 02 Arena.

A spokeswoman said Thursday that the 19-year-old pop star was given oxygen and took a 20-minute break.

During the performance, he walked off stage after complaining of being "light of breath." His manager came out and and told the crowd that the singer would return to finish the show.

The "Baby" singer is in London to perform four concerts at the O2 arena. He was widely criticized for arriving late to his first show Monday.

But fans and their mothers didn't seem to mind.

This was the third of the four shows.