Police have arrested an Islip man after he allegedly drove drunk Tuesday night and crashed, leaving his passenger critically injured.

Investigators say 42-year-old Thomas Turck hit a guardrail on Montauk Highway in Great River just before midnight. The passenger, 44-year-old Lisa Scott of West Sayville, was taken to Southside Hospital with serious head injuries.

Police say neither of the car's occupants was wearing seat belts.