The collision took place in Fairfield County in Danbury around 1:55 a.m., Sunday in the southbound lane of the highway just north of Exit 7.
According to state police, Danielle Dempsey, of Danbury, was driving a 2005 Honda Accord southbound on Route 7 when a 2018 Dodge Challenger driving in the wrong direction on the highway struck her vehicle head-on.
Dempsey was pronounced dead at the scene.
The driver of the Challenger was identified as Charles Connors, age 33, of New Haven County of Milford, state police said.
Connors, who suffered serious injuries, was transported to Danbury Hospital.
The crash is under investigation.
Anyone who may have witnessed the crash or has footage of the crash is asked to contact Trooper Matthew Dogali at 203-267-2200 or at matthew.dogali@ct.gov.
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