Investigators say this accident is the result of an elderly woman losing control of her car before crashing it in the Trader Joe's.
Up to 15 people, customers and workers, were being treated for various injuries. Some of the victims were taken to Nassau University Medical Center and Winthrop University Hospital.
The car struck at least one person and caused extensive damage to the front of the store.
"I looked back and realized what had happened someone drove through the front of the store, and the fact that it happened is unexplainable," said Eric Lemberg.
Most of the people that were injured were standing in a cashier line when the car came through.
One man got pinned between the car and the wall, but is expected to survive.
Investigators said there was chaos when they arrived.
"We had some people that were not conscious prior to our arrival, a lot of bumps and brusies," said Kevin Klein with the Oceanside Fire Department.
The driver of the vehicle did not suffer any major injuries.
Four people were still being treated for their injuries at area hospitals Friday night, one of them was listed in critical condition.