Boston police defended its communication protocols Tuesday after two city councilors said the department’s primary radio channel failed for 30 minutes on the same night that the city saw four separate shootings in Dorchester .

Councilors Ed Flynn and Erin Murphy said the radio’s main channel failed for 30 minutes, a malfunction that required officers to respond to shootings “without reliable communication tools.”

According to Mariellen Burns, Boston Police Department’s chief of internal & external communications, the “radio system itself was not offline, one channel was impacted.”

When the channel was fixed, officers resumed using it, according to Burns.

“We have an existing protocol/operational backup that if one channel has an issue officers are notified to switch to another channe

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