The 5 p.m. crash at mile-marker 337 closed all eastbound and westbound lanes, PA Turnpike officials said. It was not immediately known when the scene would be cleared.
Helicopter footage obtained by 6abc shows a tanker truck on its side, spilling fuel onto the highway.
Hazmat crews were also called to the scene, a spokesperson with the Montgomery County Department of Public Safety confirmed to Daily Voice.
Injuries were unknown.
Officials were urging motorists trapped in the crash queue to dial *11 (star 11) and provide a dispatcher with a milepost location and vehicle description.
As of 10 p.m., a center barrier was removed, allowing stranded drivers to exit the turnpike.
This is a developing story. Check back for more.
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