WASHINGTON — More members of Congress on Friday reported receiving letters containing suspicious substances, including Sens. Ted Cruz of Texas and Susan Collins of Maine, both Republicans.

Some lawmakers said that their staff members had opened the mail with the substances in their home district offices, exposing a widening number of people to potential danger. Senate and elections officials have said that the letters have so far tested negative for hazardous substances.

The incidents, the first of which was reported on Thursday, came just weeks before the midterm elections, and as election officials have reported a growing number of threats and intimidating behavior directed at them.

The mailings recalled a 2001 attack targeting lawmakers and journalists that exposed dozens of people to anthrax spores in mail containing a fine white powder, killing five people and terrorizing the country in the weeks after the Sept. 11 attacks.

The FBI, Postal Service and Capitol Police this week have been investigating the wave of mail containing the substances. The FBI said in a statement that it was working to find those responsible for the letters, but provided no information on potential suspects.

Rep. Gwen Moore, D-Wis., said in a statement that staff members in her district office in Milwaukee had opened mail with a suspicious substance “using proper protocols and precautions,” but “as a result of this incident, mail will no longer be sorted at the office.” Rep. Hillary Scholten, D-Mich., also said that her staff members had opened mail at her office in Grand Rapids containing an “unidentified white powder.”

The news station WWLP in Enfield, Connecticut, reported that an employee in the office of Rep. Joe Courtney, D-Conn., was exposed to an unknown white powder in an envelope and that he had “received appropriate medical care.”

Other lawmakers said that they had received the letters at their offices, but were able to identify the suspicious mail before opening it. Many offices were evacuated in response to the potential danger.

In addition to Cruz and Collins, Sens. Mike Rounds of South Dakota and Pete Ricketts of Nebraska, both Republicans, reported receiving suspicious letters on Friday, as did Sen. Amy Klobuchar, D-Minn., who is running for governor in the state.

Arizona’s Democratic secretary of state said Thursday that members of his staff had opened an envelope filled with white powder, prompting an evacuation of his office. He said on Friday that the substance was determined not to be harmful.

The incident was reminiscent of the anonymous mailing of powder-filled envelopes to state and local elections offices in 2023. Some of those letters appeared to have been laced with fentanyl, law enforcement officials said at the time.

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This article originally appeared in The New York Times.

By Chris Cameron/Tierney L. Cross
c. 2026 The New York Times Company