Attorney General William Barr told federal prosecutors to charge rioters and any others who committed violent crimes at recent protests with sedition.

Barr’s unusual comments came during a call with officials across the country, including U.S. attorneys.

He listed several charges prosecutors could potentially bring against protesters who became violent or rioters, including assaulting a federal officer, rioting, use of explosives, racketeering and sedition.

The New York Times reported that after Barr spoke, Richard Donoghue, a top aide to the deputy attorney general, noted that some of the cities where U.S. attorneys on the call worked were not facing violence during protests, and would likely not have to bring forward sedition charges.

Sedition law is loosely written to encompass many forms of anti-government acts. The most extreme version, which would be unlikely to be applied to the protests, outlaws conspiracies to overthrow the U.S. government. However, milder versions say sedition includes two or more people conspiring to use force to oppose federal authority, in any way hinder the enforcement of federal law or unlawfully seize federal property. A conviction on a charge of seditious conspiracy could be punished with up to 20 years in prison.

Another topic Barr reportedly brought up during the call was the potential criminal prosecution of Seattle Mayor Jenny Durkan (D) allowing the anti-police “CHAZ” occupation, in which protesters camped out near the city’s downtown for weeks.

Police officers were forced to abandon the police station located in “CHAZ,” and the area remained largely peaceful until deadly shootings in July, which prompted Durkan to take action and retake the station.

Durkan, who opposed the arrival of federal law enforcement, came under heavy criticism from President Donald Trump, who called the protesters “domestic terrorists.” He also told Durkan and Washington Gov. Jay Inslee (D) that they needed to regain control: “If you don’t do it, I will,” Trump tweeted. “This is not a game.”

Barr’s remarks about moving to prosecute an elected official for not intervening in a protest is  unprecedented.

While most of the demonstrations that have occurred in the wake of the police killing of George Floyd have been peaceful—over 93% according to the Armed Conflict Location and Event Data Project—some radical groups, as well as opportunistic looters, have committed acts of violence during protests, including deadly shootings.