All US Postal Service mail received at the Pentagon mail screening facility on Monday is currently under quarantine and poses no threat to Pentagon personnel, according to Pentagon spokesperson Col. Rob Manning.

 “On Monday, the Pentagon Force Protection Agency detected a suspicious substance during mail screening at the Pentagon’s remote screening facility,” Manning said in a statement.

Meanwhile, all U.S. Postal Service mail received at the Pentagon facility Monday is under quarantine, the Department of Defense said in a statement.

That mail poses no threat to Pentagon personnel, the statement continued.

The Pentagon’s Central Processing Center is located on the Pentagon compound in Arlington, Virginia, but not directly attached to the main building. The envelopes did not enter the Pentagon itself. source

Two envelopes suspected of containing ricin poison, one addressed to Defense Secretary James Mattis, were identified in the Pentagon’s Central Processing Center, according to a U.S. official.

Later on Monday, the Secret Service reported it had also intercepted a suspicious envelope addressed to President Donald Trump, though that envelope was not received, nor did it enter the

The envelopes found at the Pentagon’s mail center were addressed to Mattis and Chief of Naval Operations Adm. John Richardson, the official said. Those pieces of mail, flagged as part of the Pentagon’s normal processing procedures, are being examined to determine whether they test positive for the deadly poison, the FBI said in a statement.

The Secret Service said it’s also cooperating with law enforcement to fully investigate the suspicious envelope addressed to the president.

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