Justin Bieber has made a surprise appearance at the Radio 1 Teen Awards, performing three songs to the crowd.
He sang hits What Do You Mean?, Where Are U Now and Boyfriend to 9,000 screaming fans aged between 14 and 17 at the SSE Wembley Arena.
Justin Bieber also talked about his forthcoming album Purpose, due out later this month.
The Radio 1 Teen awards celebrate the achievements of "outstanding young people" as well as celebrities.
Other acts taking to the stage include Little Mix, Nick Jonas, 5 Seconds of Summer and All Time Low.
The event is hosted by Radio 1 Breakfast Show DJ Nick Grimshaw.
Other Radio 1 presenters at the event include Greg James, Alice Levine and Matt Edmondson.
Guest presenters included Idris Elba, who presented The X Factor with the prize for best TV show. Olly Murs was present to collect the award.
Although stars of stage and screen are given prizes, the main focus of the ceremony are the Teen Heroes.
These young people are selected for their selfless, brave, and exceptional achievements.
Hundreds were nominated by listeners for their achievements. The winners are selected by a panel of judges consisting of previous Teen Hero winners and Radio 1 DJs.
The Radio 1 Teen Awards are broadcast on BBC Radio 1, BBC iPlayer and the CBBC channel. You can also watch performances on the Radio 1 YouTube channel and online.