Video Watch!: Justin Bieber's Shirtless Skateboarder

A crowd of Justin Bieber fans was thrilled to see their hero skateboarding outside hisrecording studio in Miami last night -- then he took off his shirt and they went BALLISTIC.

Bieber was at the Hit Factory and a crowd of about 60 fans gathered outside.According to one witness, the group waited about five hours for a glimpse of the Biebs, when he finally obliged and came out to skateboard for a few minutes.