A Burlington woman was found guilty Monday of mailing a threatening communication to Sen. Susan Collins in October 2018, the U.S. Attorney’s Office said.

Suzanne Muscara had said the letter and envelope claiming to contain anthrax that she tried to send to Collins’ Bangor home after she voted to confirm Brett Kavanaugh to the U.S. Supreme Court was just “a joke.”

A jury convicted Muscara after just one day of trial at the U.S. District Court in Bangor. Muscara will remain held without bail until her sentencing, News Center Maine reported.

Muscara told FBI agents that the white powder in the letter was baking soda and she thought the letter was funny even though it claimed to contain anthrax.

The letter was intercepted by the U.S. Postal Service, which had started screening the senator’s mail after she had received another letter two days earlier claiming to contain poison. Collins was a target of threats during and after the tense buildup to her pivotal vote in support of Kavanaugh, who had been accused by multiple women of sexual misconduct during his high school and college years.

Inside the envelope Muscara sent was an Aetna insurance flyer with a handwritten note reading: “Anthrax!!! HA HA HA.” There was also a drawing of a person with two Xs for eyes and a tongue sticking out with an arrow that read: “You.”

Muscara does not dispute that she sent a letter to Collins on Oct. 17, 2018, but she said the letter was not threatening. When she was questioned by the FBI she said she thought it was just a joke.

Collins’ husband, Tom Daffron, received a different threatening letter alleging to contain the toxin ricin on Oct. 15, 2018. That letter was postmarked with a Washington state location and the sender has yet to be found.

Muscara was identified as the sender of the second letter by a fingerprint the FBI found on the outside of the envelope. Authorities arrested Muscara at her Burlington home on April 5, 2019.

Muscara’s letter was intercepted in the Hampden mail sorting facility by a postal inspector.

United States Postal Inspector Troy Dumond said during his testimony Monday that “a chunk of white powder fell on the floor” as he was thumbing through Collins’ and Daffron’s mail, News Center Maine reported.

Dumond described the substance as “bright, white powder, a lot of it.” The letter was taken to the state facility in Augusta for further testing. Dumond said there was no media coverage of the event and that he didn’t submit a report because officials didn’t want any copycats.

“It wasn’t a threat, I just thought the note itself was funny,” Muscara said in an FBI interview that was replayed in court Monday.

She also told FBI agents she didn’t even know who Collins was because she doesn’t pay attention to politics. She said she had heard about the hearing for Kavanaugh and about people protesting Collins’ vote to confirm him.

Kavanaugh angrily denied the sexual misconduct allegations, and pressure mounted on Collins from both sides to either support or reject the nominee. Protesters swamped her offices in Portland and Washington, D.C., and dozens were arrested during demonstrations in the nation’s capital.