San Jose police described a chaotic scene inside a Wal-Mart, where a man crashed his car through the storefront and began attacking people inside, injuring four.
"People were running out of the store, people were crying," San Jose Police Officer Albert Morales told the Mercury News. "People were just confused about what was going on."
One shopper told the newspaper that other customers tried to hold down the man. About 70 people saw the attack, police said.
The man, said to be in his 30s, was arrested after a brief struggle with police, Morales told The Times. The San Francisco Chronicle reported he was undergoing mental evaluations and drug tests. His name was not released.
Authorities are still investigating what prompted the attack late Sunday morning.
"We don't know if there was an intended target or not," Morales told The Times.
The red two-door car driven by the man ended up 10 to 20 feet inside the store, Morales said. The man exited the vehicle, picked up some sort of blunt object from inside the store and began the assault.
One of the customers suffered a serious injury and was taken to a local hospital, Morales said. Three others were treated for non-life-threatening injuries.
Sharon Kaye said the man's car sideswiped hers as she was driving in the parking lot. She told the Mercury News the man drove through the lot before crashing into the store.
"Oh, my goodness, he's going to hurt someone," Kaye recalled thinking to herself.
When the first police officer arrived, Kaye told him that he needed to call for backup.
"I stood there shocked," she told the newspaper. "It was very scary."
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