Both drivers were injured in the crash, which occurred at 1:49 a.m. between Exits 18 and 19, according to Assistant Fire Chief Brian Meadows.
Firefighters from Westport and Fairfield responded.
Engine 5 arrived and found a two-car crash involving an SUV and a flatbed tow truck, with the SUV sustaining heavy damage, Meadows said. Firefighters from Westport and Fairfield secured the vehicles in place and treated both drivers for injuries until EMS arrived, he said.
All three travel lanes were shut down, and Connecticut State Police was on the scene to investigate and control traffic.
The last Fire Department unit cleared the highway at 3:17 a.m.
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