The Maine Warden Service is investigating a serious ATV crash in West Bath that critically injured the driver.

Gifford T. Campbell, 38 and his passenger, 38-year-old Krista Gallagher, both of Bath, were injured in the crash on Hill Road just before 6 p.m. Wednesday.

Campbell was taken by life flight helicopter to Central Maine Medical Center in Lewiston with a serious head injury. He was in critical condition Thursday morning.

Gallagher was taken to Maine Medical Center in Portland for treatment of head injuries. She was in satisfactory condition Thursday morning.

Neither was wearing a helmet, according to the warden service.

Investigators will try to determine if speed and alcohol were factors in the accident. Members of the warden service’s reconstruction team will reconstruct the accident.