Cops are looking for a hit-and-run driver who struck a bicyclist on Christmas night, leaving the victim in critical condition and his bike mangled.

Police say 39-year-old Hector Rapalo was going northbound on Route 111 in Central Islip on his bike around 10:45 p.m. when a car hit him from behind. He was just blocks away from his house and was not wearing a helmet.

Rapalo was flung from the bike and smacked his head on the ground, according to authorities.

Police are looking for a dark-colored vehicle, possibly a Honda, with low wheels. Suffolk Deputy Inspector Gerard McCarthy says the car may have front-end damage.