Now Mahwah and Suffern police are conducting a joint investigation.
Sgt. Michael Blondin got the driver to his car and administered first aid after finding him in a snow bank around 4 a.m. Saturday near the Exit 66 ramp, Police Chief James Batelli said.
"He was in convulsions, unable to feel his leg and [turning blue]," Batelli said.
New York authorities were notified because of the proximity to the state line. The vehicle's final resting place was in Suffern, the chief said.
The man was taken to Good Samaritan Hospital, where he was being treated for hypothermia and other medical conditions.
One of three women he was with was also taken to Good Sam after complaning of hypothermia, Batelli said.
Police found the women -- two from Garfield and one from Cliffside Park -- after one of them called from the scene, the chief said. The other two had cellphones that were damaged by the water, he said.
The women told responding officers they'd been off-roading with the man when the vehicle went into the river -- and they couldn't find him.
Blondin en route to the scene when he spotted the man in the snow.
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