LINTHICUM, Md. (CBSDC/AP) — A BWI airport official say a canister of pepper spray left in a trash can near a checkpoint was to blame for the evacuation of two concourses on Monday.

Jonathan Dean, a spokesman for Baltimore-Washington International Thurgood Marshall Airport, says concourses A and B were cleared Monday morning after people noticed an irritant in the air near the checkpoint shared by the two concourses.

The concourses reopened less than hour later.

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