The accident, in Bridgeport between exits 27 and 27A, occurred at about 6:20 p.m., DOT said, and motorists should expect big delays in the area.
It's unknown when the accident scene will be cleared.
Traffic was backed up to Fairfield on the northbound side of I-95, with stop-and-go rubber-necking delays reported on the southbound side, too, according to the CT Department of Transportation.
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