Four congressional offices opened envelopes last week that appeared to contain a dangerous powder. Investigators say it was salt.
An Illinois man was charged Monday, Oct. 26, 2026, with mailing hoax letters containing a white granular substance to four members of Congress, according to a federal criminal complaint.
What was in the hoax letters?
Three of the letters included a handwritten note that simply laughed at the recipient, and one sent to a senator’s office told staff to enjoy the gift, according to the complaint.
Preliminary testing found no chemical or biological toxins. The man told investigators he used salt in the hoax letters because it looked like anthrax. Salt grains can resemble other white powders at a glance.
The letters were postmarked Oct. 19 in Springfield, Illinois, and arrived at the lawmakers’ district offices between Oct. 21 and Oct. 23. The complaint does not identify the members of Congress who received them. Springfield, the state capital, is about 100 miles east of Quincy.
Who is charged in the hoax letters case?
The complaint identifies the man as Matthew G. Unglesbee of Quincy, Illinois. FBI agents interviewed him at his home Oct. 25, and he admitted mailing the four letters, according to the filing. Quincy is a city of about 40,000 people on the Mississippi River in western Illinois.
He has not been convicted and is presumed innocent unless proven guilty. It was not immediately clear whether he has an attorney. The complaint, filed in federal court in central Illinois, lays out the government’s allegations but has not been tested in court.
How did investigators find him?
An anonymous tip reached the FBI’s National Threat Operations Center on Oct. 16. The tipster said he overheard Unglesbee discussing the mailings in a restaurant and provided his name, address and date of birth.
The tip came three days before the letters were postmarked, according to the dates in the complaint. The complaint does not explain how the tipster learned of the plan before the letters were mailed, or whether the FBI acted on the tip before they arrived.
The envelopes themselves also carried Unglesbee’s name and home address as the return address, the complaint says. Including a real return address made the sender easy to trace.
Why are hoax letters taken so seriously?
Even hoax letters with harmless powders trigger emergency responses, building evacuations and testing that can cost thousands of dollars and frighten staff. Federal law makes it a crime to send material meant to look like a biological weapon, even if it is harmless. Penalties for such hoaxes can include years in prison, along with orders to repay the cost of emergency responses.
Fears run high because of the 2001 anthrax attacks, when letters containing real anthrax were mailed to news organizations and two U.S. senators. Five people died and 17 others were sickened. The attacks, which came weeks after Sept. 11, 2001, sparked widespread fear and led to major changes in how mail is handled.
Since then, congressional mail has been screened and hoax letters have led to numerous federal prosecutions.
Threats against members of Congress have also risen sharply in recent years, according to the U.S. Capitol Police. Lawmakers from both parties have called for more security for members and their staff.
What happens next?
The case will proceed in federal court in central Illinois. Prosecutors will have to prove the allegations. The government has not said what punishment it will seek.
Officials have not said whether the four lawmakers’ offices were evacuated when the envelopes were opened.
For investigators, the case is a reminder that even hoax letters can carry real consequences.
