The packages were found in the Eberhardt-Findley Building, which houses both the North American Aerospace Defense Command (NORAD) and the U.S. Northern Command, in Peterson Air Force Base. Employees on Thursday morning described the boxes as seeming "out of place," and so 1,500 people were sent home for the day.
Officials sealed off a 500-foot safety zone while they brought in a team of military dogs to investigate the packages. KKTV reported that security was also boosted in neighboring buildings and the north gate going into Peterson AFB was closed until early afternoon.
In the course of the investigation, an Air Force spokesperson released a statement saying "preliminary test results of the package indicated that there is not a positive test for a nuclear, biological or chemical element contained within the package." The packages were then removed from the facility to be examined further, and the safety perimeter was removed.
It turned out the "suspicious" packages were just ordinary office supplies.
NORAD, a US-Canadian organization, did not have its operations interrupted during the incident. The NORAD control room is currently set up at Cheyenne Mountain, a temporary relocation brought on by renovations performed at their headquarters in the Air Force Base. Cheyenne Mountain had served as their HQ before they moved to Peterson in 2006.