Justin Bieber sings karaoke while vacationing with Floyd Mayweather

Justin Bieber treated his fans with a special surprise by giving an impromptu performance during karaoke night.

The 21-year-old singer, who is vacationing in Bora Bora with Floyd Mayweather, decided to stop at his hotel's bar during their karaoke night and sing for his fans, reports TMZ.com.

Bieber sang 'What Do You Mean' before getting on piano and playing 'Let It Be,' which was witnessed by 25 people.