The crash happened in Litchfield County on Route 8 in Harwinton at about 10:50 a.m. on Sunday, Oct. 30, Connecticut State Police said.
A 2011 Nissan Rogue was traveling south in the right lane of two near the Exit 42 on-ramp when, for an unknown reason, it veered into the right shoulder, struck a rock wall, and overturned, police said.
The driver, a 31-year-old Winsted man, was ejected from the Nissan, and the passenger, a 38-year-old Norwich man, was entrapped in the vehicle, authorities said.
Police said the two men were hospitalized for treatment of serious injuries.
An investigation into the crash is ongoing.
Police asked anyone with information about the crash to call Trooper DiNunzio at 860-626-7900 Ext. 5029.
Click here to follow Daily Voice Fairfield and receive free news updates.