One woman was killed and four other people were injured in a two-vehicle crash Sunday in Mattituck, Southold Town police said.
The identities of the victim and the injured have not been released.
Police said the fatal crash occurred at the intersection of County Road 48 and Westphalia Road at about 4:15 p.m., police said.
Police said a gray 2014 Ford sport utility vehicle was headed west on County Road 48 when the driver failed to stop for a red light and rear-ended a gray 2017 Honda Civic that was stopped.
A front-seat passenger in the Honda, identified only as a 23-year-old woman, died of her injuries, police said.
Police said the Mattituck Fire Department, Cutchogue Fire Department and Riverhead Volunteer Ambulance Corps transported three victims to Peconic Bay Medical Center in Riverhead with undisclosed injuries. Another victim, a woman, was airlifted to Stony Brook University Hospital, police said.
Additional details were not immediately available.
Police said the investigation, including investigators from the Suffolk County district attorney's office, is ongoing.