The victim of a deadly assault that took place Monday night in Yankton has been identified as 33-year-old Timber Rose Cournoyer. Following an investigation into Cournoyer’s death, 31-year old Adrian Lund of Sioux City was arrested and charged with second degree murder, aggravated assault domestic, and possession of a controlled substance. Officers responded to a call regarding an assault at a residence and found Cournoyer, who was badly injured. She was taken to Avera Sacred Heart Hospital where she later died.