Power is back on at Denver’s emergency communications center, restoring 911 and non-emergency phone lines that went down at 3:40 p.m., according to the Denver Department of Public Safety.

Calls were routed to neighboring jurisdictions during the outage, which lasted approximately 40 minutes.

City officials are looking into the cause of the outage and why a backup generator didn’t turn on during the outage, said spokesperson Kelly Jacobs.

This is a developing story and may be updated. 

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