A boat with four passengers rammed a dock and a lift on an Iron Range lake, killing a Burnsville woman and injuring three others, authorities said Sunday.

Ann Marie DeLanghe, 54, was pitched into the water, the Sheriff’s Office said, and several people on shore helped retrieve her. She was taken to a Duluth hospital in critical condition and later died from her injuries.

Speed and alcohol use by the boat’s operator, Brian DeRoche, 50, of Duluth, were factors in the nighttime crash Saturday on Dinham Lake, 20 miles south of Eveleth, according to the St. Louis County Sheriff’s Office.

DeRoche is being investigated for criminal vehicular homicide, a release from the sheriff’s office said.

Ernest DeLanghe, 57, of Burnsville, and Cindy De­Roche, 45, of Duluth, were also on the boat.