The three-vehicle crash occurred on southbound I-95 between Exits 7 and 6 in Stamford, closing the left lane, DOT said.
The accident was reported at about 4:55 p.m., DOT said.
Traffic was already backed up more than 2 miles to Exit 9 at the Darien border, DOT said.
It was not known when the accident scene would be cleared, DOT said.
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