Eversource Energy officials said crews responded to West Main Street in New Britain for a reported problem with an underground electric cable.
The New Britain fire chief said there was a fire underground involving some wires that run through a conduit.
The fire caused some CO gases, forcing a manhole cover to pop off.
The chief said this has happened in the past and that it is not uncommon.
West Main Street is closed at this time.
There is no threat to the public.
No injuries have been reported and no services are being impacted at this time.
Stay updated with Eyewitness News as more information becomes available.
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