The Field's mass shooting: emergency medical services response.

The EMS response generally adhered to national guidelines for MI. The activation of EMS and the hospital preparedness program was relevant. Important findings were communication shortcomings; inherent lack of readily available ambulance resources in the initial critical phase; uncertainty regarding the number of perpetrators; uncertainty regarding number of casualties and social media rumors that unnecessarily hampered and prolonged the response. The incident command had to use non-standard measures to mitigate potential challenges.