An armed man demanding to speak to the Wisconsin governor was arrested in the state capitol, posted bail, and returned - only to be arrested again.
The shirtless man, who has not yet been identified, was taken into custody on Wednesday afternoon for illegally carrying a firearm in the building.
But he posted bail and returned that evening with an assault-style rifle.
Governor Tony Evers, a Democrat, was not in his capitol office at the time, according to a spokeswoman.
The man, who was carrying a holstered handgun, approached the office around 15:00 EST (19:00 GMT) on Wednesday and demanded to see Mr Evers.
Citing police, the Washington Post reported he had a leashed dog with him and had appeared at the security desk outside the governor's office.
A single police officer sits at the desk on the building's first floor, which also houses a conference room and offices for the attorney general.
Weapons can be brought into the building if they are concealed and the carrier holds a valid permit. The man did not have a permit and was arrested by capitol police.
But after being booked into the local Dane County Jail, he posted bail and returned again to the capitol grounds just before 22:00 EST carrying a loaded automatic rifle. The building closes at 19:00 EST.
Officers spoke with him, asked to search his backpack and found a police baton, again in violation of the concealed weapons permit law, the Post said.
The would-be assailant had been taken into custody a second time on Wednesday night for a psychiatric evaluation, Tatyana Warrick, a Wisconsin Department of Administration spokeswoman, told the BBC. Ms Warrick could not confirm if he remained in custody.
Police for the city of Madison said in a police report: "The subject was taken into protective custody and conveyed to a local hospital."
The governor's office and Dane County officials could not immediately be reached for comment.
Public and elected officials across the US currently face a rising number of threats in violence.
The incident comes more than a year after Mr Evers appeared on the hit list of a gunman previously accused of zip-tying and fatally shooting a retired county judge at his Wisconsin home.
The hit list with Mr Evers' name on it also included those of Senate Minority Leader Mitch McConnell and Wisconsin's Democratic governor Gretchen Whitmer, the target of a kidnapping plot in 2020.