One of the vehicles became engulfed in flames after the southbound crash near Exit 40B just before 10 p.m.
Hongying Tian of Avon, Conn., was transported to Norwalk Hospital, where she was pronounced dead.
Tian was driving a Volkswagen Passat at a high rate of speed when the vehicle hit the median, breached the guardrail, struck a tree and then traveled across both lanes before coming to rest on the side of the road near trees and brush, state police said.
The other cars were struck by flying debris: A 2012 Infiniti driven by Tyler Batalia, 21, of Bedford, and an Audi driven by Ryan Pilla, 44, of New York City with two passengers aboard. None of the four in the two cars suffered injuries, police said.
The highway was closed for several hours while police conducted an accident investigation.
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