The Los Angeles County sheriff says a bystander's cell phone footage taken last month showing a deputy violently tackling a woman while she filmed a man being handcuffed, then pepper-spraying her in the face, is "disturbing," and community groups on Wednesday called for the department's new chief to hold his agency accountable.

The June 24 incident outside a WinCo Foods grocery store in the city of Lancaster follows several cases that have drawn scrutiny to the department amid allegations of excessive use of force by its deputies. It's also testing the reform efforts of the new sheriff, Robert Luna, a former Long Beach police chief who has vowed to overhaul the nation's largest sheriff's department since taking it over in December after defeating incumbent Alex Villanueva.

Both officers were pulled off field duty, Luna said during an afternoon news conference, and could face discipline ranging from letters of reprimand all the way up to dismissal if misconduct is found. He didn't identify the deputies.

Luna said he didn't learn about the encounter until six days after it occurred. The department released footage from the deputies' body-worn cameras on Monday.

Luna said he had seen the body-camera video as well as bystander video that spread on social media.

"It's disturbing. There's no ifs and buts about it," the sheriff said.

At his news conference, Luna said the deputies were responding to a robbery in progress after receiving a 911 call from a store employee saying that two customers were assaulting "loss prevention employees."

Luna said it appeared that the man and woman were both involved in the confrontation inside the market but that their relationship wasn't clear.

In the over five-minute bystander video obtained by CBS News, a deputy can be seen grabbing the woman by the neck and violently throwing her to the ground while she is filming the man's arrest on a cellphone. The deputy then pepper sprays her.

The deputy puts his knee on the woman's back while he handcuffs her.

In bodycam video, the woman is heard yelling "I can't breathe," while the man tells the other deputy that the woman has cancer. 

The woman was treated at a hospital after complaining of pain to her eyes after being pepper-sprayed, and she also had scrapes to her arms, the sheriff said.

The man was arrested and cited for resisting for delaying an officer, petty theft or attempted petty theft and interfering with a business, while the woman was cited for assaulting an officer and battery after assaulting loss prevention personnel, Luna said.

It wasn't immediately clear whether they had lawyers who could comment for them.

Tom Yu, an attorney representing the deputy who tackled the woman, says his client took her "down to the ground due to her being resistant."

"Deputies are trained to take suspects who resist to the ground in order to gain compliance and to safely handcuff the suspect," Yu said in an email on Wednesday.

Yu said his client "approached" the woman to detain her. She replied, "you can't touch me," the lawyer said.

"This was the beginning of the ensuing use of force," Yu wrote.

Yu also declined to release his client's name, reiterating that the department had not done so either.

The sheriff said his department has opened an investigation into the deputies' use of force and had notified the county's Civilian Oversight Commission and also federal monitors, who are overseeing reforms that the department agreed to in 2015. That agreement settled federal allegations that deputies in the Antelope Valley, including Lancaster, had engaged in excessive use of force and racially-biased policing that included disproportionately stopping or searching Blacks and Latinos.  

In:
• Los Angeles