The accident, reported at 10 a.m. Thursday, is between Exit 23 for Route 1 and Exit 24 for Black Rock Turnpike, DOT said.
It is not clear how long it will take to clear the accident scene, DOT said. Traffic delays of more than 5 miles are reported back to Exit 18 in Westport for the Sherwood Island Connector, DOT said.
"Traffic along the Post Road in Fairfield will remain congested as a result of accident on I-95," Fairfield Police Chief Gary MacNamara said via Twitter at about 11:50 p.m.
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