Three men accused in a plot to kidnap Michigan Gov. Gretchen Whitmer have been indicted on charges of conspiracy to use a weapon of mass destruction, federal prosecutors said Wednesday.
The new charges against Adam Fox, Barry Croft Jr., and Daniel Joseph Harris center on an alleged plan to blow up a bridge near Whitmer's vacation home in order to hinder police, according to a superseding indictment.
Fox and Croft allegedly inspected the underside of the bridge for a place to put explosives in September while they were on their way to conduct "nighttime surveillance" of that home, the indictment alleges.
Croft and Harris also allegedly blew up or tried to blow up improvised explosive devices, including a test of how well shrapnel would work against people. Fox is accused of ordering $4,000 worth of explosives from an undercover FBI agent.
The plan to blow up a bridge had previously been disclosed in an indictment. Croft and Harris were also indicted on additional firearms-related counts.

"We are looking forward to defending the case in court," said Croft's attorney, Josh Blanchard, but declined further comment Wednesday evening. Attorneys listed as representing Fox and Harris did not immediately respond to requests for comment.
Six people were arrested on federal charges in October in the alleged plot to kidnap Whitmer, which was foiled. Authorities say they were members of a militia group or identified with the "three percenter" anti-government movement.
One of the people charged federally, Ty Garbin, pleaded guilty in January and agreed to cooperate with law enforcement. Garbin has been described as a leader of the "Wolverine Watchmen" militia group.
Eight others alleged to be members or associates of that group have been charged in state courts, including some who are accused of helping with surveillance of the governor's vacation home as part of the kidnapping scheme.