It happened around 8:30 p.m. Wednesday, July 19, in the town of Litchfield, according to Connecticut State Police.
The 17-year-old girl was driving northbound on Route 8 near Exit 41 when her car ran off the left side of the road.
Her car rolled over before hitting a tree.
The teen, a resident of Torrington, was transported to Hartford Hospital with life-threatening injuries.
Anyone with information regarding the crash is encouraged to contact Trooper Thomas Schaefer from CSP Troop L by calling 860-626-7900 or emailing thomas.schaefer@ct.gov.
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