SHIN POND, Maine (NEWS CENTER) --  A four-year-old boy who was injured in an ATV accident Monday has died. The Maine Warden Service says Tanner Morse died last night at Eastern Maine Medical Center.

Morse, who lived in Searsport, was riding an ATV on his grandfather's property in Shin Pond. He was apparently trying to go up an incline when the ATV flipped over and landed on top of him. The Warden Service says the little boy's father found him lying on the ground unconscious.

This incident remains under investigation by the Maine Warden Service in cooperation with the Penobscot County District Attorney's Office.