Six men were arrested and accused of plotting with a militia group to kidnap Gov. Gretchen Whitmer of Michigan, the authorities announced on Thursday.
The men, who the F.B.I. said espoused anti-government views, had talked about taking Ms. Whitmer, a Democrat, hostage since at least the summer, according to a criminal complaint filed in federal court and unsealed on Thursday.
They had surveilled Ms. Whitmer’s vacation home in August and September and indicated that they wanted to take her hostage before the presidential election in November, Richard J. Trask II, an F.B.I. special agent, said in the criminal complaint. He said the F.B.I. believed the men were planning to buy explosives this week for their attempt.
Several of the men had talked about creating a society in which they could be “self-sufficient” and one said he wanted 200 men to storm the Statehouse in Lansing, Mich, the complaint said.
Over the summer, the men gathered for firearms training and combat drills and tried to make explosives; in July, one of the men said the group should take Ms. Whitmer hostage and move her to a “secure location” in Wisconsin for a “trial,” the agent said.
“When I put my hand on the Bible and took the oath of office 22 months ago, I knew this job would be hard,” Ms. Whitmer said on Thursday, in reaction to news of the arrests. “But I’ll be honest, I never could have imagined anything like this.”
The F.B.I. said it had learned so much about the group by intercepting encrypted messages and because it had undercover agents and confidential informants working with the group.
The six men — five of whom live in Michigan and one of whom lives in Delaware — were charged with conspiracy to commit kidnapping, which can carry a life sentence. More details were expected at a news conference later on Thursday with the state’s attorney general.
Ms. Whitmer has been the subject of right-wing protests for measures she imposed to control the spread of the coronavirus.
In April, President Trump had openly encouraged protests against social distancing restrictions in Michigan and several other states with stay-at-home orders, just a day after his administration announced a set of guidelines for how the nation’s governors should carry out an orderly reopening of their communities on their own timetables.
In a series of all-caps tweets that started just after a Fox News report on the protests, the president declared, “LIBERATE MICHIGAN!” and “LIBERATE MINNESOTA!” He also lashed out at Virginia, where the state’s Democratic governor and legislature have pushed for strict gun control measures, saying: “LIBERATE VIRGINIA, and save your great 2nd Amendment. It is under siege!”
The Democratic presidential nominee, Joseph R. Biden Jr., said that he and his running mate, Senator Kamala Harris, had spoken with Ms. Whitmer.
“There is no place for hate in America, and both of us have been talking about this for some time, about how white supremacists and these militias are a genuine threat,” he told reporters at the airport in Phoenix, according to a pool report.
Mr. Biden said that he believed Mr. Trump’s “LIBERATE” tweet had encouraged militias.
“Why can’t the president just say, ‘stop, stop, stop, stop, and we will pursue you if you don’t, so, stop’ ?” he asked.