Maine wardens say a 19-month-old boy has died from injuries suffered when an all-terrain vehicle operated by his father flipped over.
Wardens say the father had three children on the ATV when it toppled backward Sunday while ascending a hill on private property in Windham.
Wardens say the youngster was taken to Maine Medical Center, where he died Monday.
The identities of the young victim and his father weren't immediately released. The Maine medical examiner's office planned an autopsy Monday.
The Maine Warden Service will be working with the district attorney as the investigation unfolds. Windham police and Cumberland County deputies assisted.
Wardens say they don't believe helmets were being worn.