Motorised Cyclist Riding Dangerously 13 April 2013

I was turning left when this guy on a motorised bicycle suddenly starts to cross the zebra crossing when I'm on it. He then starts making hand gestures. and in my rear view mirror, I see him challenging me to stop my car. I just ignored him since there was no accident. I even raised my hand as a sign of apology but he seems to get angrier. That rear view video will be uploaded soon when I get the video from my rear camera. He then starts to make a call, WHILE he is still riding. And as can be seen, when he overtakes me at the next junction, he shows me the middle finger and then he goes back to a pedestrian crossing and goes to a pavement and starts riding there. He's riding dangerously and he starts to make signs at me? Doesn't make sense.