The crash occurred on the Northeast Extension in Carbon County 5:45 p.m. near Mahoning Valley Exit #74. Photos show the tractor's cab and trailer stretched across both sides of the median.
Motorist Chris Jones detailed the scene in a Facebook post.
"The accident involved a southbound tractor trailer that jackknifed to its left as the tractor jumped partway over the wall, badly damaging the wall itself with large holes," he writes.
"The northbound side is completely littered side to side for several hundred feet with vehicles, bits and pieces of vehicles, and all different size pieces of the wall itself."
Both sides of the highway were stopped to secure a landing zone for a medical chopper, Jones said.
At least six state troopers and three ambulances responded — "and that’s just the traffic that accessed the scene from the north end," Jones asid.
"The northbound lane was blocked from mile 88 all the way to the Lehighton Exit on 476 and whatever caused the tractor trailer to jackknife and jump the wall, it destroyed so much of the wall that chunks of all sizes up to as large as car tires were everywhere, scattered among trashed vehicles and debris, completely blocking the roadway for several hundred feet."
Jones recalled the wheels on a pickup truck nearly falling off, with at least three other cars whose airbags deployed completely destroyed.
The New Jersey driver in one of the cars involved was killed just before 6 p.m. north of the Lehigh Tunnel, WFMZ says citing the county coroner's office. His name was not immediately released.
The highway was closed for several hours.
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