A New Hampshire man sustained life-threatening injuries after crashing his car off the highway early Sunday morning.

Troopers responding to Route 101 eastbound just before 3:30 a.m. for a report of a vehicle off the road found a 2014 Jeep Grand Cherokee several hundred feet in the woods near the Exit 5 off-ramp, according to New Hampshire State Police.

Officials say the driver and lone occupant of the car, 34-year-old Alex J. Sitton of Candia, was found partially thrown from the vehicle with severe injuries.

Sitton was transported to an area hospital in critical condition.

A preliminary investigation determined Sitton, for reasons unknown, lost control of the Jeep while traveling on the Exit 5 off-ramp and veered left off the roadway into a wooded area. The Jeep struck several trees before overturning and coming to rest on its roof.

Crews worked for hours to remove the car from the tree line. The Exit 5 off-ramp was closed for approximately four and a half hours.

It reopened to traffic just before 8 a.m.

The cause if the crash remains under investigation by New Hampshire State Police.

No further information was immediately available.

This is a developing story. Check back for updates as more information becomes available.

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