The interior floors of the Centennial Mills warehouse are fully collapsed after a Sunday, Aug. 2, fire, putting it at risk of fully collapsing. (Dennis Weis/Portland Fire & Rescue/Courtesy)Investigators believe there is a high likelihood that human remains are buried in the rubble of Portland’s scorched Centennial Mills warehouse after human-remains detection dogs alerted during two searches of the building. Two additional searches on Aug. 6 both produced positive alerts, prompting investigators to believe potential human remains may be buried beneath the collapsed building. Officials have not said who the potential remains could belong to or how many people may be involved. Further investigation will be needed to determine whether human remains are present.