Abby Mueller of Houston, Texas, was ejected from the family's 24-foot motorboat around 2:45 p.m. Tuesday and run over by the propeller, which severed one leg between the ankle and knee. She was flown to a Boston hospital. Her condition was not immediately known late Tuesday.
The Maine Warden Service says the girl's father, 44-year-old Robert Mueller, had five children with him, one being towed on a tube, when the boat struck a rock inside an area marked with hazard buoys.
Mueller suffered minor injuries. He is the father of three of the children and two are family cousins from Woodstock, Conn.
Officials don't believe alcohol was involved.