You do know cell phones are radios
Methinks the police frequency is a tad bit more ‘clear’ than cell tower freqs.
Collections of radios, actually. CDMA, GSM, HSPA, LTE, WiFi, Bluetooth ...
If I were designing a resilient communications system for emergencies, I would put a wireless access point in every emergency vehicle, police station, and firehouse and form mesh networks. Possibly using packet radio on the emergency band as backup.