The offices of Republican Sens. Ted Cruz and Susan Collins received envelopes containing a “white powder” Friday, bringing the number of lawmakers targeted in the suspicious-mailing campaign to more than a dozen.
The FBI, US Postal Inspection Service and US Capitol Police are investigating the letters. Some of the envelopes were intercepted before they reached their intended recipients.
“This afternoon, my Houston office received a suspicious piece of mail containing a white powder substance,” Cruz, R-Texas, wrote on X. “The FBI, Houston Police and Fire Department, and U.S. Capitol Police responded swiftly.”
Cruz described the incident as “deeply concerning,” saying that attempts to intimidate political opponents “have no place in our country.”
A similar letter addressed to Collins, R-Maine, was delivered to her Portland office, triggering an evacuation and emergency response. Another letter sent to her Washington, DC, office was intercepted by US Capitol Police.
“Thank you to the Portland police, the Portland fire department, the hazmat team, and the FBI [for] their quick and courageous response,” Katie Brown, Collins’ chief of staff, said in a statement to local outlets. “This was the fourth attack targeting Sen Collins’ office or home in the past two months.”
“Despite escalating political rhetoric and harassment, we will continue our work for the people of Maine.”
Cruz and Collins are both facing close midterm reelection contests.
Capitol Police warned Senate offices about the letters Thursday and distributed an image showing what the suspicious envelopes looked like.
Sen. Mike Rounds, R-S.D., said his staff did not open a “suspicious piece of mail” delivered to his Sioux Falls, South Dakota, office Friday because of the law enforcement warning.
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“I am grateful for the U.S. Capitol Police, who intercepted other letters and sent out a warning allowing my team to recognize this letter before opening it, and to the Sioux Falls Police Department,” Rounds wrote on X. “I am also grateful for all of my team members, who work tirelessly on behalf of South Dakotans despite the risks involved.”
The senator added, “This situation is deeply concerning and follows a trend of intimidating tactics that impact our team members. This has no place in our nation. America is better than this.”
The Senate warning included a photo of one suspicious envelope. It was postmarked “DSA” and listed a return address at 75 Maiden Lane, a Financial District building that the Democratic Socialists of America once included on its membership forms.
“DSA has not occupied this office address since 2013,” a representative for the organization said in a statement. “We are also no longer headquartered at 75 Maiden Lane.”
In addition to the three Republican Senate offices that received letters Friday, at least 15 congressional offices held by Democrats and approximately 26 state election offices have also been targeted, according to NBC News.
New York Reps. Laura Gillen, Tom Suozzi and Ritchie Torres, along with Senate Minority Leader Chuck Schumer, D-NY, are among the Democratic lawmakers who have confirmed receiving letters.
The FBI has not identified the white powder, describing it only as “an unknown substance.”
Congressional offices have previously been targeted with contaminated mail, most notably during a series of anthrax attacks in 2001 that sent the deadly bacteria to Senate offices.
One of those letters was delivered to the office of then-Senate Majority Leader Tom Daschle, D-SD, in October of that year. Staff members were forced to seek medical treatment, and an entire building was later decontaminated.
The anthrax mailings killed five people and sickened at least 17 others.
Letters containing ricin, a poison, have also been mailed to Senate offices in the past, but didn’t result in any deaths.