Some emergency phone calls to the Santa Rosa Police Department went unanswered for an unknown amount of time early Monday after a blown circuit board disrupted service.

Power to the department's communications center went down at about 9:15 a.m.

The power failure stopped incoming phone lines, police radio system and computer-aided dispatch system, said Rhonda McKinnon, police technical services manager.

City staff scrambled to reroute all 911 calls to the Sonoma County Sheriff's Office dispatch center and officers began using a sheriff's radio channel.

It took about 90 seconds to switch over to the sheriff's systems, McKinnon said.

While calls to 911 from city phones were forwarded to the Sheriff's Office, some direct calls to the police dispatch number, 528-5222, couldn't get through because the call-forwarding function was not working, McKinnon said.

By 10:40 a.m., AT&T had remotely forwarded the calls to the Sheriff's Office.

The circuit board was replaced by Monday evening and regular service was restored, McKinnon said.

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