A Wisconsin man pleaded guilty on Wednesday to a reduced charge for his role in a foiled plot to kidnap Michigan Governor Gretchen Whitmer, handing another victory to prosecutors who have viewed the scheme as domestic terrorism.

Michigan prosecutors accused Brian Higgins, 54, of aiding the conspiracy by surveilling the Democratic governor’s vacation home. As part of a plea deal, he admitted in Antrim County court that he attempted to provide material support for terrorism and agreed to cooperate with prosecutors, Michigan Attorney General Dana Nessel said in a statement.

Higgins, who faces up to five years in prison, will testify against four men who will go on trial on related charges later this year.

Michael Naughton, an attorney listed for Higgins, did not immediately return a request for comment.

Prosecutors initially charged Higgins with providing material support for a terrorist act, along with the four men who are also accused of firearm violations. The remaining defendants could face 20 years if convicted of the terrorism charge alone.

They are among more than a dozen suspects who were arrested in connection to the plot in October 2020. Last year, seven men were convicted and sentenced for related crimes. Two others were acquitted of charges.

In the previous cases in Jackson County and federal court, prosecutors argued the alleged conspirators were affiliated with right-wing militia groups who opposed public health measures that Whitmer imposed during the early days of the Covid pandemic.

The group planned to break into Whitmer’s vacation home, kidnap her and take her at gunpoint to stand “trial” on treason charges, all part of an effort to spark a “second American Revolution” prior to a contentious 2020 presidential election, prosecutors said.

Adam Fox, the alleged ringleader, and Barry Croft, Jr., were sentenced to 16 years and more than 19 years, respectively, after being convicted of domestic terrorism, conspiracy to kidnap and other crimes in a second federal trial.

Two others on trial with them were found not guilty in April 2022. The same jury failed to reach a verdict for Fox and Croft, resulting in a mistrial.

Two other men, Ty Garbin and Kaleb Franks, pleaded guilty and cooperated with federal prosecutors. They were sentenced to 2 1/2 years and four years in prison, respectively.

Three other men received sentences of between 7 and 12 years after they were convicted in state court of playing supporting roles in the plot.