DULUTH (AP) - Duluth's main post office has reopened after a woman wearing a military gas mask walked into the building with a duffel bag and package.

Police closed the post office for much of the day Monday after taking the woman into custody. It took authorities several hours to determine the bag and package were harmless.

Police spokesman Jim Hansen says the woman was taken to the St. Louis County Jail on possible charges of disorderly conduct and concealing her identity.

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