PITTSBURGH (KDKA) — Nearly 15,000 customers in Westmoreland County and surrounding areas are without power and it may take several days before service is restored.

Allegheny Power reports on its website that for customers in Allegheny, Fayette, Greene, Washington and Westmoreland counties, the lights may not come back on until Saturday.

Even so, crews were out late Wednesday night cutting through fallen trees and working to get the power back on.

A line of storms Wednesday evening spawned a tornado that ripped apart homes, snapped trees like twigs and knocked down phone and utility lines.

The Red Cross set up a warming shelter at the Hempfield Township Municipal Building in the Greensburg-Hempfield Business Park on Woodward Drive.