Tactical Emergency Medical Services (TEMS) is out-of-hospital care given in hostile situations by specially trained practitioners. It is distinct from the care given by medics in war zones, as TEMS generally refers to care rendered by civilians. Tactical Medics are Emergency medical technicians (EMT), paramedics, nurses, and physicians who are trained to provide life-saving care and, sometimes, transport in situations such as tactical police operations, active shooters, bombings, and natural disasters (though rarely the latter).
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Tactical Emergency Medical Services Wikipedia(Text) CC BY-SA