At least five people were killed and dozens more injured in a crash in Pennsylvania early Sunday involving a tour bus, two tractor-trailers, and passenger vehicles.

Pennsylvania Turnpike spokesman Carl DeFebo confirmed about 60 patients were transported to three local hospitals after the multi-vehicle crash.

 

There were at least five confirmed fatalities, he added.

A “prolonged closure” of the turnpike is likely, he said. He added that officers were still on the scene, with a major response required.

DeFebo said it was premature to speculate about the cause of the incident. "We just don't know," he told NBC News.

The crash happened in Westmoreland County, near Pittsburgh, around mile marker 86.

The incident happened westbound, he said, but debris was scattered over the eastbound section of road.

An 86-mile stretch of the turnpike remained closed between New Stanton at Exit 75 and Breezewood at Exit 161, DeFebo tweeted.

This is a developing story, please check back for updates.