WASHINGTON – An elementary school in Northwest has reopened after it was evacuated Wednesday, following the discovery of a mailed letter containing white powder.

No hazardous materials were found.

Three people, who weren’t students, were exposed to the powder at Adams Elementary School off 19th Street Wednesday morning, D.C. Fire and EMS reports. None at the school showed any symptoms.

The Washington Post reports the substance was flour.

Suspicious packages were also reported just before 11 a.m. at Oyster Elementary School in the 2800 block of Calvert Street and at the Willard Intercontinental Hotel on Freedom Plaza. The hotel was cleared later Wednesday morning.

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