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FBI Dallas said on November 13 that it has identified William Earl Cade as the person who mailed seven threatening white powder letters from the Dallas area, a case it solved with investigative genetic genealogy. According to the FBI release, Cade died in April 2026, before investigators put a name to him.
The case began in February 2024, when a sealed envelope was found leaking white powder. Agents eventually linked seven letters to the same sender. Each held white powder and violent threats, and each was addressed to high-level US government officials or members of their families. Testing found the powder was not hazardous.
A handwriting assessment concluded the letters were most likely written by one person. The FBI said it exhausted traditional investigative methods before turning to genetic genealogy, which compares DNA left at a crime scene with genealogy databases to find relatives of an unknown person and build a family tree toward a suspect. Investigators believe Cade acted alone and have not identified any other suspects. The release does not name the officials who received the letters or give further details about Cade.
The bureau has used genetic genealogy since March 2018 and says the method has helped solve nearly 250 cases across 30 states. FBI Dallas started its own program in 2020 and now runs four dedicated teams that work with local police departments on their cold cases.
The announcement came nine days after the FBI arrested a suspect in a separate and much larger mailing campaign. As Al Jazeera reported on November 4, Robin Patrick Martin, 67, of Oklahoma City, is accused of sending more than 700 white powder letters to state and federal officials, including members of Congress and election officials. One was addressed to FBI Director Kash Patel.
In the Martin case, the FBI cited video of him at Postal Service locations in Oklahoma City, Dallas and San Antonio, along with his fingerprints on the letter to Patel. Initial testing found that powder was yeast or flour. Martin is charged with conveying false or misleading information or hoaxes and with mailing threatening communications. Neither announcement links the two cases, and the FBI says it believes Cade worked alone.
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