Federal authorities in the United States are investigating a series of letters containing suspicious substances sent to state election offices and congressional offices across the country, raising security concerns less than three weeks before the November 3, 2026, midterm elections.
The Federal Bureau of Investigation (FBI), US Postal Inspection Service and US Capitol Police are working together to investigate the mailings, identify those responsible and intercept additional letters before they reach their intended destinations. Officials have warned recipients to treat suspicious mail as potentially hazardous.
Suspicious Mailings Reported Across Multiple States
The investigation covers letters and packages sent to election administrators, secretaries of state and members of Congress in several states.
Authorities reported that some of the mailings contained an unidentified powdery substance. Similar packages prompted evacuations at election offices in Louisiana and Oklahoma, while postal authorities intercepted a suspicious package addressed to the Ohio secretary of state's office.
Several other states, including Idaho and Florida, also reported that election offices had received suspicious letters or that the mailings had been intercepted before delivery.
The full number of affected offices remains unclear, and investigators have not publicly identified the person or people believed to be behind the mailings.
Congressional Offices Also Targeted
The suspicious mailings have extended beyond election administration offices to members of the US Senate and other elected officials.
The office of Senator Lisa Blunt Rochester of Delaware reported that a letter containing a suspicious substance had been intercepted by Capitol Police. Senator Alex Padilla of California said the Postal Service stopped a suspicious package before it reached his office, while Senator Kirsten Gillibrand of New York also reported that postal inspectors intercepted suspicious mail addressed to her office.
Further reports published on October 16 indicated that additional congressional offices had received or been notified about similar mailings. The FBI and postal inspectors are investigating the incidents as part of what authorities believe may be a connected series of cases.
The Senate Sergeant at Arms notified Senate offices about the threat and said law enforcement agencies were working to intercept additional letters. The notice cautioned that some mailings could still reach their intended destinations.
Authorities Examine Unknown Powdery Substances
Investigators have not established that the substances found in all the letters are dangerous.
The FBI confirmed that some of the mailings contained unknown substances and said it was working with law enforcement partners to respond to each incident and determine who was responsible.
In Wisconsin, the state's Elections Commission reported receiving a suspicious letter, but testing found that the powder inside was not hazardous. This highlights the need to investigate each mailing rather than assume that every suspicious substance poses the same risk.
In Louisiana, officials evacuated a facility after a suspicious package arrived. Authorities later reported finding no evidence of harmful substances associated with the incident. Nevertheless, the investigations have continued because officials do not yet know the origin or intent behind the wider series of mailings.
Concerns Ahead of the November Midterm Elections
The incidents come as election officials across the United States prepare for the November 3 midterm elections, when voters will decide contests that will determine control of Congress and several important state and local offices.
Election administrators are responsible for preparing ballots, managing voting procedures and ensuring that election results are processed accurately. Threats directed at their offices can disrupt routine operations and create additional security demands during an already busy period.
The National Association of Secretaries of State and the National Association of State Election Directors have condemned threats against election officials, stressing that those responsible for administering elections should be able to perform their duties without fear for their safety.
The mailings have also revived concerns about similar incidents during previous US election cycles. Suspicious packages were sent to election offices in earlier years, prompting investigations and additional precautions for staff handling mail.
Although the current investigation has not established a motive, the timing has heightened concern among officials responsible for protecting election infrastructure and personnel.
Federal Agencies Work to Prevent Further Deliveries
The FBI and US Postal Inspection Service are continuing to investigate the source of the letters and determine whether the incidents are linked.
The agencies are also coordinating with election offices and congressional security teams to respond to reported mailings and prevent additional suspicious packages from reaching their destinations.
Officials have advised recipients to follow established safety procedures when dealing with suspicious letters or packages. Staff should not handle unidentified substances and should alert the appropriate security or emergency authorities.
The investigation remains ongoing, and authorities have not publicly announced an arrest or identified a suspect.
With the midterm elections approaching, officials face the challenge of protecting election workers and public offices while ensuring that preparations for voting continue without unnecessary disruption.
For now, investigators are focused on identifying those responsible, determining the nature of the substances and establishing whether the mailings represent a coordinated campaign targeting election officials and lawmakers.
