The firefighters were dispatched at 2:30 p.m. to the Merritt Parkway southbound between Exits 41 and 40, said Assistant Fire Chief Brian Meadows in a statement.
Westport firefighters arrived at the scene and found an area about 300 feet by 100 feet on fire in the area of the West Rocks overpass, Meadows said.
Norwalk firefighters were already on the scene. Westport Firefighters worked along with Norwalk Firefighters to extinguish the fire.
A total of three lines were stretched and operated. Fire crews remained on the scene, checking for hot spots and overhauling, he said.
The Connecticut State Police was on the scene to provide traffic control.
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