APPLETON, Maine — A 43-year-old Rockport woman was killed Saturday night when the snowmobile she was riding and one driven by her son struck each other.

Jan M. Richardson was pronounced dead at the scene, according to a news release issued by the Maine Warden Service.

The crash occurred shortly before 11:30 p.m. Saturday in a field off West Appleton Road in Appleton.

Richardson was visiting friends in Appleton with her son Josh Berry, 20, of Rockport. Richardson and her son were riding the snowmobiles in a nearby field when the crash occurred, according to the warden service. Richardson was not wearing a helmet.

Berry was taken to Waldo County General Hospital in Belfast, was treated for his injuries and released on Sunday, according to a hospital spokesperson.

The Union Fire and Rescue departments responded. Cardiopulmonary resuscitation was performed at the scene on Richardson.

Speed and alcohol appear to be factors in the crash, the warden service reported. The incident is under investigation by the warden service, the Knox County Sheriff’s Office and the Knox County District Attorney’s Office.

Wardens Michelle Merrifield, Mark Merrifield and Warden Sgt. Scott Thrasher went to the scene, as did Wardens Josh Smith and Eric Blanchard of the Maine Warden Service Forensic Mapping Team.