York Regional Police are asking witnesses to come forward after a cyclist was struck in a hit-and-run crash in Vaughan.

The 46-year-old man suffered serious head injuries after he was struck by a westbound transport truck on Highway 7 at the on-ramp to Highway 427 around 5:15 p.m. on Thursday.

The driver did not stay at the scene.

Police say the cyclist was not wearing a helmet. His injuries are serious but he is expected to survive.

Anyone with information is asked to contact police.