The incident occurred at 6:37 a.m. Friday on the southbound side of the highway between the rest stop and Exit 40, said Capt. Stephen Rabel with the Milford Fire Department.
Milford Firefighters arrived on scene and found the tractor-trailer off the road and into the wooded area. The driver of the vehicle, whose name has not yet been released, was pinned in the vehicle and had to be extricated, Rabel said.
The extrication was complicated by having to remove trees and brush as well as having to deal with spilled diesel fuel and a nearby stream.
Paramedics provided advanced life support to the patient during the extrication process.
"Despite the extraordinary efforts by the fire department the driver ultimately succumbed to his injuries," Rabel said.
The highway is down to one lane of traffic and will remain that way pending an accident investigation by the Connecticut State Police that has gone into the afternoon.
DEEP officials are also on scene due to hazardous fluids that leaked out of the truck, a boom has been placed downstream to contain the spill, he added.
This is a developing story. Check back to Daily Voice for updates.
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