persons provide free service to motorists in distress, and secure lanes of traffic, provide emergency medical assistance, request tow trucks for vehicles in inconvenient or dangerous locations, remove debris from the roadway after a crash, and resolve minor disabled vehicle problems, such as flat tires, jumpstarts, or pushing a disabled vehicle out of travel lanes. Many of these patrols work directly with the State Police and Highway Operations departments of their state, and respond to assistance when a citizen calls 911 for minor roadside assistance duties. See also Traffic police Traffic warden State police Police Chief of police Constable References Highways Law enforcement units State agencies of the United States Transportation government agencies of the United States Law enforcement fr:Histoire de la police#Polices autoroutières