(Tualatin, OR) -- Human remains that were found in the Tualatin River last month by a kayaker have been identified. Detectives are investigating the incident as a murder. The Washington County Sheriff's Office used DNA to determine the two pieces discovered August 8th and 9th belonged to 34-year-old Ezequiel Avila-Ruiz, who was known to camp in the area. Detectives are now looking for anyone with information about Avila-Ruiz after he was last seen on the evening of July 31st in Hillsboro.