Teen sensation Justin Bieber treats fans to Boyfriend sing-along

London: Justin Bieber`s fans were treated to a sing-along of his latest single `Boyfriend` with an impromptu performance of the hit track outside a TV studio.

Much to the delight of his fans yesterday the 18-year-old singer surprised a host of his supporters waiting to catch a glimpse outside the `Tonight Show With Jay Leno` studio in Burbank, California, by blasting out his hit track, reported Contactmusic.

Bieber was greeted by screams and cheers before he got out and started interacting with his delighted supporters before introducing his guitarist Dan Kanter and launching into a stripped back version of the song.

"We played acoustic for all the fans waiting outside the NBC gates. Great to see how much JB appreciates his fans.

Bieber entered the building and was interviewed by host Jay Leno before playing `Boyfriend` for the second time in one day followed by his impromptu performance.

It`s not the first time the `Never Say Never` hitmaker has treated fans to a surprise performance. He sang `Boyfriend` to supporters on a balcony in Paris and at his hotel in Mexico earlier this month.

Universal Music headquarters in the French capital saw a traffic jam due to Bieber singing to hundreds of fans with Dan strumming on his guitar in the background.