The 911 system in Hamden was unavailable for part of Monday afternoon.
The police department experienced an interruption to its telephone services, including 911, according to police officials.
All 911 calls were rerouted to the New Haven Police Department, which dispatched Hamden emergency personnel to any emergency calls that came in during the outage.
The 911 system and all phone lines were repaired by 4 p.m., police said.
It's not clear what caused the outage.