The State Medical Examiner’s Office says the woman who was found dead on Linn-Buchanan Road near Walker on Wednesday was murdered. She has been identified as 29-year old Crystal Marie Gaffney of Waterloo. An autopsy shows she died as a result of head trauma. The Linn County Sheriff’s Office says 36-year old Shaun Hogan of Waterloo has been taken into custody and has been charged with Gaffney’s death. He is being held without bond in the Linn County Jail on the charge of First Degree Murder. Hogan will make his initial court appearance Friday morning. Hogan and Gaffney have a young child together. Their relationship status at the time of the incident in not known. Gaffney is the mother of all three children who were involved in Wednesday night’s Amber Alert. The Linn and Buchanan County Sheriff’s Offices and the State Division of Criminal Investigation are continuing to investigate the incident.