The woman was lying on the beach when she was hit.
People on the beach at Rio Grande Ave in Wildwood on Wednesday heard the commotion around 3:30 p.m.
"Everybody was gathering around screaming, yelling at the person in the truck, 'Stop! There's somebody under your truck! You hit somebody!'" said Rose Simone of Chalfont, Pa.
Emergency responders were called to the beach for a report of a person struck by a vehicle.
No details have been released by police about what led up to this incident - or who was behind the wheel.
Photos and videos from the scene show people gathered around a white pickup truck, marked Wildwood Police, and it appears they're trying to help someone under the front of the vehicle.
"There's someone under there," a woman can be heard saying in the video provided by Simone.
"A bunch of guys came around that were in the area and they said we have to lift the truck, the front of the truck to get her out," said Simone.
"Come over. We're going to try to lift it up," said one man in the video, referring to the truck.
"It was an accident clearly. But one that probably could have been avoided," said Simone.
EMS and other help arrived and the woman was taken away on a stretcher.
The victim's boyfriend says she suffered multiple broken ribs, three fractured vertebrae and a lung injury.
She is expected to survive.
Wildwood Mayor Ernie Troiano said Thursday the investigation is ongoing, calling it an "unfortunate situation."