US federal authorities charge Oklahoma man over hundreds of powder-filled letters sent to officials

Federal authorities in the United States have charged an Oklahoma man, Robin Martin, in connection with hundreds of letters containing nonhazardous white powder that were mailed to public officials before the 2024 and 2026 elections. The case became public through a Federal Bureau of Investigation (FBI) court filing released on Tuesday.

The charges

Martin faces charges of conveying a hoax and mailing threatening communications. He was expected to make his first court appearance on Tuesday afternoon in Oklahoma City. Online records do not list an attorney who could comment on his behalf.

What the powder was

According to the FBI filing, the powder proved to be yeast or flour. Not all of the letters, however, had been fully tested.

Earlier developments

Last month, federal authorities announced they were investigating letters containing “suspicious substances” that had been sent to congressional and election offices across the country. Recipients were urged to treat the mailings as “potentially hazardous”. The FBI and the US Postal Inspection Service were handling the investigation.

A message from the Senate sergeant at arms, obtained by the Associated Press, said law enforcement officials were working to intercept any further letters, but that “it is possible that some letters may reach their destinations”.

On Tuesday the FBI referred questions to the US attorney’s office. The Postal Inspection Service did not immediately respond to an AP email seeking comment.