MADRID, Maine (AP) A Connecticut man was killed when he lost control of an all-terrain vehicle and was thrown off, causing fatal injuries, officials said.

Sebastian Constantini, 47, of Oxford, Connecticut, was leading a small group late Monday afternoon while returning to Rangeley after a day of riding, the Maine Warden Service said.

Constantini, who was not wearing a helmet, suffered severe head and neck injuries, wardens said.

His brother, who was riding another ATV, rendered first aid while a third ATV operator went for help, but an ambulance crew was unable to save Constantini, who died at the scene, wardens said.