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 to authorities, police said on Saturday.

The woman, who was not publicly identified, surrendered at the Los Angeles Police Department's Northridge 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.

Police already had been coordinating with Walmart security to review footage from security cameras in the store when the woman turned herself in.

She is accused of unleashing a can of pepper spray on a crowd of bargain hunters at a Walmart in L.A.'s Porter Ranch neighborhood 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 if prosecutors decide to pursue the case, the woman could be charged with battery.

The incident was one of several outbreaks of violence around the country late Thursday and on Friday that gave an air of desperation to this year's launch 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.