Jackknifed tanker truck jams traffic on Pa. Turnpike near Valley Forge

VALLEY FORGE, Pa. (WPVI) -- A crash involving a jackknifed tanker truck jammed traffic on the Pennsylvania Turnpike.

It happened at 8:20 a.m. Friday in the westbound lanes, west of the Valley Forge interchange at mile marker 323.6.

Images from Chopper 6 HD showed a silver jackknifed tanker truck.

The truck appeared to have struck the concrete barrier dividing the eastbound and westbound sides of the turnpike.

A sedan with some front-end damage was parked in the shoulder a short distance away.

There was no immediate word what led to the crash or number or extent of any injuries.

All westbound lanes were blocked as police investigated and crews worked to clear the wreckage and debris from the crash.

Motorists were advised to seek alternate routes.

Stay with Action News and 6abc.com for more information as it becomes available.