Illinois man charged with mailing white-powder letters to members of Congress

Matthew Unglesbee, 37, is charged with mailing threatening communications and with false information and hoaxes in federal court in central Illinois, CBS News Chicago and NBC News reported. According to an FBI affidavit, three of the letters held a handwritten note reading "HA HA," and he told agents the substance was salt. Three Chicago-area House members received the letters at their district offices, and hazmat teams responded each time, CBS News Chicago reported.

According to the FBI, Unglesbee admitted mailing the letters after hearing about earlier mailings to lawmakers, but denied any role in those. Agents found a fifth, unmailed envelope addressed to a member of Congress, the affidavit says. The case began with an anonymous tip to the FBI on Oct. 16, NBC News reported.

Why it matters: The FBI is separately investigating letters with suspicious substances sent to members of Congress and election officials in recent weeks, NBC News reported.