From the June 3, 2020, edition of Fox Business' Lou Dobbs Tonight

LOU DOBBS (HOST): The U.S. Park Police chief noted that at about 6:30 Monday evening eastern time, protesters had begun throwing bricks, frozen water bottles, and caustic liquid at police officers. He also noted that intelligence revealed there were calls for more violence against police officers. In order to suppress that violence, the U.S. Park Police warned the demonstrators and protesters to evacuate. And after the protesters continued their violence, the U.S. Park Police did use smoke canisters and pepper balls to clear the area. There was never any tear gas.