FirstEnergy Corp. says a power surge started a fire in an underground electrical vault that blocked roadways and left smoke rolling out of manhole covers in northwest Ohio's largest city.
The Blade newspaper reports at least three manhole covers flew into the air and others were smoking early Wednesday from the overnight fire.
Police and other city workers were rerouting traffic in the affected part of the city.
Workers from FirstEnergy were evaluating the damage.
A spokesman said the early assessment indicated some of the blocked roads might not reopen until Thursday.