When first responders arrived at the scene, they were met by "distraught" family members, Lt. Kraig Gray said.
The man was found in the van in about 12 feet of water by divers from the Sound Shore Fire Department, Gray said. He was taken from the van but was pronounced dead at Greenwich Hospital.
Strickland Road was closed from the train station to the I-95 underpass after the accident.
His family is from a neighboring municipality in New York State, but Gray didn't say where. He said more information about the incident will be released Tuesday.
The accident is still under police investigation, he said.
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