According to the FBI, it has thwarted a plot by militia members to kidnap Michigan Gov. Gretchen Whitmer. At least six people were involved in the alleged conspiracy.

The militia group, the agency says, had already been on its radar because its members had attempted in March to acquire the home addresses of local law enforcement officers, with the goal of attacking or killing them. 

The FBI says it collected information about the plot from informants and undercover agents. Over the summer, the conspirators allegedly began training for a potential attack on Whitmer’s vacation home or the governor’s official summer residence, according to a criminal complaint that was released Thursday. 

A federal charge of conspiracy to commit kidnapping has been filed against six people: Adam Fox, Barry Croft, Ty Garbin, Kaleb Franks, Daniel Harris, and Brandon Caserta. All of them are Michigan residents except for Croft, who is a resident of Delaware.