It happened at about 11:20 p.m. Saturday, July 24, on Long Island on Montauk Highway in Suffolk County, near the intersection of Quogue Street East in the Village of Quogue.
Quogue Police said a Nissan Maxima was westbound on the highway when it left its lane and drove into oncoming traffic, colliding with an eastbound Toyota Prius.
Four people were pronounced dead at the scene, and a fifth person was pronounced dead shortly after the crash at Southampton Hospital.
Another person was taken to Peconic Bay Medical Center, and they remain in critical condition, police said.
The identities of everyone involved are being withheld pending notification of their families.
Authorities said excessive speed may have been a contributing factor in the crash.
The crash is being investigated by Quogue Village Police detectives. They are being assisted by New York State Police, Southampton Town Police, and Westhampton Beach Police.
This is a developing story. Check back to Daily Voice for updates.
Click here to follow Daily Voice Fairfield and receive free news updates.