Power has been restored to roughly 45,000 National Grid customers who lost power in North Buffalo and some northern suburbs Saturday morning.
A company spokesman said the problem occurred in a substation in South Buffalo. The power went out about 6:30 a.m. and all customers were back on line by 10 a.m., a company spokesman said.
The power was restored in stages so not everyone was on at the same time.
National Grid is still investigating the root cause.
Power failures were also reported in Kenmore, Cheektowaga and Amherst.
The power failure caused stoplights to be out of service, and Buffalo City officials reported some traffic problems as a result. They reminded drivers that, at intersections where the lights are out, drivers should treat it as a four-way stop.