Gas is off to around 250 Eversource customers in Willimantic this morning and crews have been working through the night to restore it.
A third-party contractor was working on a gas line on Wednesday and there is air in the lines, which could blow out furnace pilot lights, officials said.
Crews have isolated the issue and gas service was shut off to all affected customers a little after midnight. Teams are working on re-energizing the system.
Eversource will call customers to tell them when they can expect their gas to be back on.