Authorities are investigating letters containing “suspicious substances” sent to multiple Capitol Hill offices, according to a notice distributed to congressional staff.
The Senate Sergeant at Arms said law enforcement officials are working to intercept additional letters before they are delivered, though some may still reach their intended destinations, according to a memo obtained by Politico.
The Capitol Police, FBI, and U.S. Postal Inspection Service are involved in the investigation. The notice said additional letters had been mailed to addresses across the country, including lawmakers’ state and district offices.
A separate notice sent to House staffers said the letters contained a “suspicious white powder.” The House Sergeant at Arms urged staff to “remain vigilant and follow safe mail handling procedures to help protect staff from potentially harmful materials.”
The FBI is investigating suspicious mailings containing unknown substances sent to state election offices and other government offices nationwide, prompting evacuations and law enforcement responses ahead of the November midterm elections.
The federal agency confirmed the investigation to the Washington Examiner, saying some of the letters contained an unknown substance and that authorities are working to identify those responsible.
“The FBI and U.S. Postal Inspection Service are investigating a series of suspicious mailings sent to various addresses nationwide, including Secretary of State offices and their related election offices,” the bureau said. “Some of the letters contained an unknown substance and we are working closely with our law enforcement partners to respond to each incident.”
Incidents have been reported in Louisiana, Oklahoma, and Ohio.
In Louisiana, an employee at the secretary of state’s office in Baton Rouge discovered a white powder inside a package around 12:20 p.m. The state’s Elections Division was evacuated, and officials shut off the building’s air conditioning as a precaution.
Oklahoma’s State Election Board received an envelope containing suspicious white powder on Tuesday, prompting the evacuation of its office and a response from the Oklahoma Highway Patrol, Oklahoma City Fire Department, and Oklahoma National Guard.
Ohio Secretary of State Frank LaRose condemned the threats, saying they would not interfere with election preparations.
“We have a duty to the citizens of Ohio to deliver secure and accessible elections, and these kinds of cowardly threats will not deter us from that mission,” LaRose said.
The National Association of Secretaries of State and the National Association of State Election Directors issued a joint statement condemning the incidents and warning against threats to election workers.
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“Those who administer our elections should never fear for their safety while carrying out their essential duties,” the organizations said, adding that election officials are working with law enforcement and security partners to protect personnel and facilities.
The groups said election offices have security measures and contingency plans in place to respond to potential threats while maintaining election operations.