Two men were injured about 2 p.m. Thursday when a car and mail truck collided head-on on Ward Road, north of Niagara Falls Boulevard.
John J. Fazzolari, 18, of 2535 River Road was taken to the Erie County Medical Center by MercyFlight, where he was listed in critical condition.
Philip G. O'Connor, 24, of 101 Banko Drive, Depew, who was driving a U.S. Postal Service truck, was treated in DeGraff Memorial Hospital in North Tonawanda, then released.
Deputy Patrick Freeman of the Niagara County Sheriff's Department said Fazzolari's southbound car apparently crossed into the northbound lane, hitting the truck.
Volunteers from the St. Johnsburg Fire Company assisted.