One CS grenade will taake out a city block, and those down wind will feel it. It only takes 13ppm in air to get a response. I seriosly doubt that he had access or used a Military Grade CS device. I might think he rolled a couple of Pepper Spray Cannisters down the isle with a rubberband holding them open, but I dounbt it was CS, but it is possible. Some states still sell CS MACE, and just spraying it into a room on the walls will really reak havock on the next person walking in.