Old Lyme — A man was flown to the hospital by Life Star helicopter Wednesday evening after his SUV rode up a set of guard rails off Route 1 then down an embankment into the wetlands below.

The crash occurred shortly before 9 p.m. in the area of 299 Boston Post Road. Old Lyme firefighters, responding with police, found a Ford Escape on its side with the unidentified driver trapped inside. The SUV was resting in a pool of water in a heavily wooded area.

Old Lyme Assistant Fire Chief Tom Risom said it appeared the vehicle veered off the road and up onto the guardrails at one of the entrances to Stones Ranch Military Reservation.

Firefighters used straps to hold the vehicle in place while the driver was cut free and treated at the scene by emergency medical personnel. The man, who was conscious when pulled from the SUV, was taken by ambulance to a nearby field on Grassy Hill Road to the awaiting helicopter. His condition was unknown late Wednesday.

The cause of the crash is under investigation.