FAIRFIELD — A teen suffered serious injuries in a crash on Fairfield Woods Road Wednesday night after an apparent medical episode, police officials said.

First responders were dispatched to Fairfield Woods Road between Melville Avenue and Stratfield Road for a reported crash around 7 p.m., police said.

Lt. Anthony Granata said an 18-year-old man was driving a Jeep Wrangler west on Fairfield Woods Road when he appeared to have suffered some sort of medical incident, causing him to hit a small retaining wall and tip over.

Granata said several police officers were the first on scene and found the teen unconscious in the driver’s seat. He said the officers “forced entry into the Jeep through the rear window and roof” to get to the driver.

Medics transported the teen to St. Vincent’s Medical Center, where he was listed in critical condition later Wednesday night, Granata said.

The crash remains under investigation by the Fairfield Police Crash Reconstruction Unit.