http://tooldtowork.com/2011/01/ems-response-to-the-tucson-shootings/
In Arizona, police patrol services are primarily provided by the Arizona Department of public Safety on Interstate highways and maybe state highways ... other areas are served by County Sheriffs and city police. Fire service is provided by city fire departments, fire districts, and volunteer fire companies. Wildland fire protection is provided by USFS, BLM, Nps, BIA, and USFWS on non military federal lands. Wildland fire service on military lands is provided by DOD or state natl guard or a federal wildfire agency. State Forestry covers unincorporated non federal lands. Local fire companys cover wildlands inside citys and small towns. Ambulance service is provided by a mixture of fire departments and private ambulance companys etc. Wilderness search and rescue services are typically organized by County Sheriffs. Medevac helicopters are operated by the State DpS, private companies, phoenix city, and at least 1 federal agency (Grand Canyon}
There are some County FDs - and probably some County ambulance services also. Ambulance services on military sites are typically provided by the base FD. Ambulance services on Indian Reservations is usually provided by tribal or local agencies.
Indian reservations are protected by a mixture of BIA, tribal, private, and local agencies. (for structural fire and wildland fire and technical rescue and EMS and police services - there might be some fbi and bia police in the picture also on some tribal lands - MOUs cover the various arrangements - we presume - 11/11/2024)