Threatening letters bearing a Portland postmark similar to those that arrived at some Senate and House district and state office last week were intercepted Monday at a Washington area Senate screening facility – and each were similarly found to contain no hazardous material, say officials.
So far, in all of the instances made public, authorities determined that the powder was either corn starch or harmless mixture of corn starch with some other ingredient.
But in an update on Monday, to Senate offices on Monday, Senate Sergeant-at Arms Terrance Gainer writes that, “Arrival of the letters in DC today is further evidence of the bothersome commitment of the individual or group behind these mailings.
“All staff, here in DC and in the state offices, should remain vigilant and follow our established mail-handling protocols,” advises Gainer.
And in a separate notification Monday, House Sergeant-at-Arms Paul Irving advised House offices that, “although no suspicious mail addressed to House Members with a DC address has been delivered, it is important to remain vigilant for any mail or package that appears out of the ordinary or contains any threats.”
Irving’s memo also notes that House mail operations have been alerted to the potential threat and are continuing to process mail destined to the House Office Buildings “in a secure environment.”
Irving also tells the House offices that “while staff should be vigilant with mail bearing a Portland postmark, you should be on the lookout for any suspicious mail, regardless of where it originated.”
A federal criminal investigation, in coordination with the U. S. Capitol Police, is ongoing.