Four people were hurt in two separate all-terrain vehicle accidents in Oxford and Washington counties Saturday.

Maine Department of Inland Fisheries and Wildlife spokesman Edie Smith said John and Rebecca Stanhope of Robbinston were injured at 6 p.m. on Johnson Tree Farm Road in Robbinston, 35 miles north of Machias.

Rebecca Stanhope’s vehicle collided with a vehicle driven by Doug Smith of Princeton as she attempted to pass his vehicle. John Stanhope was a passenger on the Smith vehicle.

The Stanhopes were treated at Calais Regional Hospital for broken ribs and internal injuries.

Peter Harrington of Sumner was seriously hurt when his vehicle hit a tree on Abbott Hill Road in Sumner at about 9 p.m. 

His passenger, an 11-year-old stepson, received minor injuries. Harrington was transported to Central Maine Medical Center where he is in critical condition.

Harrington or his stepson were not wearing helmets, Smith said.