Firefighters responded to a fire early Wednesday morning at Casella Waste Systems in Westbrook.
Westbrook firefighters say the fire started around 1:30 a.m. in a tractor-trailer outside the facility.
The fire then spread to two other tractor-trailers.
The fire did not spread to any buildings.
Firefighters say the tractor-trailers were filled with compacted trash and kept reigniting.
No one was hurt, and there is no word yet on what caused the fire.
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