Discuss what to do after the initial response
The first officers to arrive to the scene will not stop to help injured persons. Expect rescue teams comprised of additional officers and emergency medical personnel to follow the initial officers. These rescue teams will treat and remove any injured persons. They may also call upon able-bodied individuals to assist in removing the wounded from the premises.
Once you have reached a safe location or an assembly point, you will likely be held in that area by law enforcement until the situation is under control and all witnesses have been identified and questioned. Do not leave until law enforcement authorities have instructed you to do so.