The school said Wednesday in a statement that it received the "suspicious package" on Monday.

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The suspicious package containing the powder was postmarked Sept. 25, according to the Centers for Disease Control.

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If you see a suspicious package or activity on the platform or train, do not keep it to yourself.

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If you receive a suspicious package, don't open it, isolate it, evacuate the area around it and call police or a postal inspector.

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The Brighton line, which carries B and Q trains through southern Brooklyn, was closed for an hour Tuesday morning after a report of a suspicious package near the Avenue H subway stop.

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Her staff were suspicious of the package and contacted Strathclyde Police.

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