Correction: This post has been changed to reflect that The Washington Post has not received any suspicious mailings.
At least five Senate and House district offices have received threatening mail in the last three days with a suspicious powdery substance — and similar letters with harmful materials may exist, congressional law enforcement officials warned.
The most recent letter was discovered Wednesday in a Senate state office, according to Senate Sergeant at Arms Terrance W. Gainer. The letters have tested negative for harmful substances and there have been no injuries, he said.
Gainer and House Sergeant at Arms Paul D. Irving informed all congressional offices via e-mail Wednesday to treat incoming mail with care and to be on the look-out for letters with “a suspicious powdery substance.”
“The author of these letters has indicated that additional letters containing a powdery substance will be arriving at more Senate offices and that some of these letters may contain an actual harmful material,” the e-mail said, adding that all of the suspicious letters included a return address in Portland, Ore.
The first letter was discovered Monday, according to Gainer. His office is cooperating in a joint investigation with the U.S. Capitol Police, the FBI, the U.S. Postal Inspection Service and the U.S. Secret Service.
“We take these matters seriously and will investigate fully,” the FBI said in a statement.
The suspicious mail comes less than a week after federal authorities arrested a Virginia man in an alleged plot to carry out a suicide bombing at the U.S. Capitol. Amine El Khalifi of Alexandria will be held in jail pending possible indictment after waiving his right to a hearing Wednesday.
Gainer dismissed speculation that the two incidents are linked. “I don’t think it has any relationship to that,” he said.
Several media outlets, including The Washington Post, were told by federal authorities to be on the lookout for suspicious letters containing a powdery substance. The Post informed newsroom personnel in a message sent Thursday morning.
Fox news has received a letter at its New York offices, as did Jon Stewart and Stephen Colbert, according to federal officials familiar with the investigation.
Read the full text of the e-mail sent to Senate offices below:
Urgent: Suspicious Mail Alert
The purpose of this message is to follow up with the entire Senate community on an earlier message today regarding threatening mail. Yesterday, a Senate State office and a House District office received threatening mail that contained a suspicious powdery substance. Those letters were tested and the substance found to be harmless. Today, another similar letter was received in a Senate State office.
The author of these letters has indicated that additional letters containing a powdery substance will be arriving at more Senate offices and that some of these letters may contain an actual harmful material. Although all letters received thus far have proved harmless, it is essential that we treat every piece of suspicious mail as if it may, in fact, be harmful.
n particular, offices should pay special attention to letters postmarked from Portland, Oregon, or with the following return address:
The MIB, L.L.C.
2413 NW Burnside
Portland, OR 97209
We are working closely with federal and local law enforcement in this ongoing investigation. In the meantime, if any mail is received from this return address, it should remain unopened and the local authorities contacted immediately, followed by notification to the United States Capitol Police Threat Assessment Section at 202-224-1495.
Terrance W. Gainer
Senate Sergeant at Arms
This post has been updated since it was first published.
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