Morales did not know the extent of the injuries to the other three people but said they were not life-threatening. A store employee was among those injured.
Shopper and witness Tianna Doan said the injured employee was a cashier who was hit with the blunt object and had a head injury.
Two other vehicles were struck in the parking lot before the Oldsmobile crashed into the store.
Sharon Kaye told the Mercury News the driver sideswiped her car as he made several runs around the parking lot before driving between poles at the entrance of the store.
"At first, I thought I may have done something to anger him while driving," she said. "But then I realized he was out to get into the store."