National Grid says hundreds are affected by power outages in the Elmwood Village Monday.
A spokesman from National Grid, Steve Brady, says a contractor not working for the gas and electric company dug into a conduit bank, causing damage to the wires inside the conduit itself.
Brady says this type of damage requires a "lengthy" repair. The outage is expected to be fixed by 7 p.m.
National Grid says it may be able to run temporary lines to some customers.
National Grid is investigating how the contractor made the error.
