be careful of what?
United States Park Police acting chief Gregory t. Monahan said in his June 2, 2020 statement: about what happened on June 1, 2020:
“At approximately 6:33 pm, violent protestors on H Street NW began throwing projectiles including bricks, frozen water bottles and caustic liquids.”
Gayle King on today’s (June 3, 2020) CBS This Morning kept classifying the protests as “peaceful” but I don’t consider throwing bricks as “peaceful.”