PETERSON AIR FORCE BASE, Colo. (AP) — Authorities say five suspicious packages that caused a lockdown at the home of NORAD and U.S. Northern Command were routine office supplies.

Spokeswoman Jennifer Thibault said the packages were found Thursday in the building where NORAD and Northern Command are based.

READ MORE: Ryan Yarwood Arrested After Eluding Police In Stolen Vehicle

Thibault said the base has a procedure for delivering packages and it was not clear if those procedures were followed. An investigation is under way to find out how it happened and how to prevent problems in the future.

READ MORE: Concessionaires Looking To Fill Thousands Of Open Positions At Denver International Airport

NORAD officials were working at their Cheyenne Mountain location at the time because of renovations being done in the building so the military says its operations were not affected.

Thibault says the office supplies were found after the packages were deemed safe and opened to find out what was inside.

MORE NEWS: What Is Sweetwater Lake, A 'Hidden Gem' That's Soon-To-Be Colorado's 43rd State Park?

(© Copyright 2013 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)