The shooting was reported just before 4 a.m. Wednesday, Sept. 14, on I-95 in Darien.
Responding officers found a vehicle just off Exit 10, near Noroton Avenue and Maple Street with three victims suffering from gunshot wounds inside, Connecticut State Police said.
Two passengers suffered life-threatening injuries and were taken to Stamford Hospital, where one later died, police said.
Authorities identified the deceased victim as 31-year-old Earl Gayle.
The other passenger, Rashawn McCalla, age 28, underwent surgery and was listed in stable condition, according to police.
The 29-year-old driver, Jovel McKenzie, stayed at the scene and refused medical treatment for a superficial wound to his right shoulder.
Troopers closed the southbound lanes of I-95 between Exits 18 and 16 while investigators combed for evidence.
Police eventually recovered ten shell casings south of the Exit 16 on-ramp, police said.
No suspects had been arrested as of 6 p.m. Wednesday, Sept. 14.
Western District Major Crimes Squad (WDMCS) has assumed the investigation.
"This is believed to be an isolated incident and there is no threat to the public at this time," the department said.
Anyone with information or dashcam video is asked to contact WDMCS at 203-696-2500.
This continues to be a developing story. Check back to the Daily Voice for updates.
Click here to follow Daily Voice Brookfield and receive free news updates.