Federal authorities are investigating a wave of letters containing "suspicious substances" mailed to congressional offices and election offices across the United States, less than three weeks before the November 3, 2026 midterm elections. The FBI, the U.S. Postal Inspection Service, and the U.S. Capitol Police are working the case after recipients were urged to treat the mailings as "potentially hazardous."
Senate offices targeted
The investigation was first disclosed in a Thursday, October 15 message from the Senate Sergeant at Arms to Senate offices, obtained by the Associated Press. The threat in Congress appeared limited to the Senate, with the House monitoring the situation. Senators notified by the FBI that they were targets included Chris Murphy of Connecticut and Alex Padilla of California, while Senate officials said senators of both parties received letters.
Senate staff were told the letters had tested negative for hazardous substances. A letter intercepted for Senator Murphy's office contained the suspicious substance, and the FBI said it is working to identify those responsible.
Election offices in at least six states hit
Election offices in Louisiana, Oklahoma, Ohio, Maryland, Mississippi, and South Dakota received suspicious mail, along with the Wisconsin Elections Commission. In Louisiana, an office was evacuated on Tuesday, October 13, after a staffer opened a package containing powder; the employee was taken to an emergency room as a precaution and the office later reopened after tests found no hazardous substances. An Oklahoma office was also evacuated. In Ohio, a package was intercepted by the Postal Inspection Service before delivery, according to Secretary of State Frank LaRose. Wisconsin's commission received suspicious mail on October 14 but did not open it, and field tests found no hazardous material.
The "DSA" return address
A picture of one envelope in the Senate security notice listed a Manhattan return address for "DSA" — a former office of the Democratic Socialists of America. The DSA said it did not send the letters and had not occupied that suite since 2013, leaving the building in January. The security notice warned staff that suspicious mail may show discoloration, powder emanating from the envelope, or postmarks that do not match the return address.
Officials respond
"Some of the letters contained an unknown substance, and we are working closely with our law enforcement partners to respond to each incident." — FBI statement
Postal Inspection Service Deputy Chief Inspector Brendan Donahue said inspectors stopped delivery of at least one mailing. The national associations of secretaries of state and state election directors said in a joint statement: "Those who administer our elections should never fear for their safety while carrying out their essential duties." Wisconsin administrator Meagan Wolfe said the mailing would have "no impact on our unwavering commitment to deliver a safe and secure election."
The episode echoes a 2023 scare in which several election offices received envelopes containing fentanyl, and the suspicious packages sent to officials in 17 states before the 2024 election. Authorities declined to say how many offices were targeted in total.
Watch: AP report on the FBI investigation into powder-filled letters sent to Congress and election offices
Music in this post's reel: Kevin MacLeod - Unanswered Questions (incompetech.com), licensed under CC BY 3.0
Sources
- Associated Press — "Authorities investigate letters with 'suspicious substances' sent to congressional, election offices"
- BBC — "Letters with 'suspicious substances' sent to US election offices"
- NPR — coverage of the Senate security notice and "DSA" return address