The victim was headed toward New Jersey in the northbound lanes of the bridge and walking along the concrete divider when she was hit by a tractor-trailer around 6:15 a.m., troopers said in a release.
The crash knocked her over the divider into the southbound lanes, where two passing cars both struck her, authorities said. She died from her injuries at the scene.
The tractor-trailer stopped at the next available exit in New Jersey while the southbound drivers continued toward Pennsylvania, according to police.
The southbound drivers may be "unaware of their involvement," they added.
Troopers said the victim was a black woman in her 30s or 40s who was between 5-foot-5 and 5-foot-8 with brown eyes and black hair with some light brown highlights.
She was wearing a multi-colored wool winter cap, a black hoodie, a blue jacket with an "FDR Services Healthcare Laundry Specialist" logo on the upper right chest, black leggings, and black boots. She also carried a small, light brown purse.
Anyone who witnessed the crash, or who may be able to identify the victim or the southbound drivers is asked to call PSP in Trevose at 215-942-3900.
Click here to follow Daily Voice Bristol and receive free news updates.