Authorities in the Tucson area on Wednesday will conduct a multi-agency exercise in multiple locations to practice responding to multiple emergency events.
Officials say the public may observe emergency vehicles heading to locations of simulated incidents.
The Pima County Office of Emergency Management says hundreds of people will participate in what are described as "realistic scenarios" involving multiple locations at various times in Tucson and other communities.
The locations will include the University of Arizona but officials aren't releasing specific locations or details about the scenarios in advance.
Separately, the American Red Cross's Southern Arizona Chapter on Friday and Saturday will conduct a mass-sheltering exercise to respond to simulated large-scale flooding.