U.S. Border Patrol Commander Gregory Bovino is under intensifying scrutiny in Chicago after he was recorded on Thursday throwing what appeared to be a tear gas canister at protesters, leading attorneys to accuse him of violating a temporary restraining order that bans the use of tear gas, pepper spray and other tactics against journalists and protesters unless under imminent threat.

The Department of Homeland Security said in a statement that Bovino was struck in the head by a rock thrown by “hostile and violent” protesters, though several witnesses challenged that contention.

On Friday, Bovino was ordered to appear before a federal judge on Tuesday.