Hillary Clinton's campaign HQ evacuated over white substance

Oct 21 (Reuters) - The campaign headquarters for U.S. Democratic presidential candidate Hillary Clinton was evacuated on Friday night after a white substance was discovered in an envelope, police said.

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The substance was first discovered by two interns at a campaign office in Manhattan and was taken to Clinton's Brooklyn headquarters, triggering the evacuation of the 11th floor, a New York Police Department spokesman said.

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A total of four people were exposed to the substance, police said, though there have been no injuries or reported illnesses. Police are testing the substance and investigating the case.