LOS ANGELES - A woman suspected of dousing fellow Walmart shoppers with pepper spray during a Black Friday-eve bargain frenzy in suburban Los Angeles has turned herself in, police said on Saturday.

The woman, who was not publicly identified, surrendered at a Los Angeles Police Department station on Friday night, about 24 hours after the pepper-spray incident, and was released on her own recognizance, police said.

She was not immediately charged or booked.

"The investigation is ongoing," police Sergeant Jose Valle told Reuters. "We still have additional victims and witnesses to interview before we determine what action needs to be taken."

The woman is accused of unleashing a can of pepper spray on a crowd of bargain hunters at the Walmart on Thursday night as shoppers waited for store clerks to unwrap a shipment of discounted Xbox video game consoles.

Authorities said the woman then grabbed one of the consoles, quickly purchased it and left the scene as fire department personnel arrived to treat about 20 people who were injured by the spray, including some children.

All those injured were treated at the scene, officials said.

Valle said the woman could be charged with battery if prosecutors decide to pursue the case.

The incident was one of several outbreaks of violence around the country late on Thursday and Friday at the start of the traditional holiday shopping season.

In northern California, a man was shot and critically wounded by robbers trying to steal newly purchased merchandise in a parking lot outside a Walmart in San Leandro, near Oakland, on Friday morning.

Elsewhere, security personnel used stun guns and pepper spray to control frenzied or disorderly shoppers.