SAN FRANCISCO (AP) — The grieving mother of a young black man shot dead by San Francisco police has filed a federal civil rights lawsuit, saying officers needlessly opened fire in an incident captured on video and circulated widely online.

Five San Francisco police officers shot and killed Mario Woods, 26, on the afternoon of Dec. 2 after they say he refused commands to drop an 8-inch knife he was carrying. Police were responding to a stabbing report in the city’s gritty Bayview neighborhood when they encountered and surrounded Woods.

Two video clips of the incident have circulated widely online, angering community leaders and activists. During community meetings this week, some have called for Chief Greg Suhr to resign and for the officers who fired their guns to be charged criminally.

Dozens of protesters marched Friday through the streets to San Francisco’s City Hall. Some of them held signs demanding Suhr’s resignation. Police stood guard from a distance.

“This happened under his watch,” said Sam Sinyangwe, 25. The crowd dispersed about 3:30 p.m., Sinyangwe said.

Suhr said the department is investigating the shooting along with the district attorney and the city’s Office of Citizens Complaints. Suhr also said the department is reviewing its “use-of-force” policies and procedures and called on the police commission to arm the department with stun guns.

Police departments in San Francisco and Detroit are the only cities with more than 500,000 residents to not arm officers with stun guns.

The five officers who fired their guns have been placed on leave pending the outcome of the investigations.

The department released the officers’ names Friday night. They are: Winson Seto, Antonio Santos, Charles August, Nicholas Cuevas and Scott Phillips. No further details on them were released.

Martin Halloran, president of the police union, said the officers acted appropriately and fired their weapons after pepper spray and the shooting of bean bags full of lead pellets failed to stop Woods.

“With innocent bystanders nearby and the erratic behavior of the subject, the threat to life was imminent,” Halloran said. “With no other options available, the officers were forced to discharge their firearms.”

Suhr said at a news conference on Wednesday that police opened fire when it appeared Woods was raising the knife and approaching one of the officers. Lawyer John Burris, who is representing Woods’ family, disputed that account Friday and showed a video clip obtained from a witness not previously seen publicly. Burris said Woods never raised his hands.

“None of the videos show Mr. Woods creating an imminent threat to anyone prior to being riddled with bullets from head to toe,” the lawsuit stated.

Woods’ mother and two brothers attended the news conference and sobbed while the video played on a large television screen. The woman who captured the incident on video could be heard pleading with Woods to drop the knife as he hobbles down a sidewalk, clutching his apparently injured left side of his body. An officer can be seen cutting off Woods’ path on the sidewalk moments before police open fire. All five officers who fired their guns have been placed on leave pending the outcome of several investigations.

Burris also displayed four photos taken of Woods at the morgue. Burris said Woods’ body had 20 gunshot wounds, including one to the back of the head.

Woods’ mother briefly spoke Friday, saying her son “was the best of me” while crying uncontrollably. Woods had recently been released from prison after serving a sentence for robbery.

“He was the best of me and redeemed himself,” Gwendolyn Woods said. “He did. He redeemed himself. He was the best of me.”

Woods’ two brothers declined comment.

Burris declined to identify the woman who captured the incident on her phone, the third known video clip of the shooting. Burris said he is unaware if the San Francisco police have seen the new video.

“This is an active and ongoing investigation,” Sgt. Michael Andraychak said. “Any new information and or new video will be followed up as part of the investigation. The department will follow up on everything that Mr. Burris spoke to at his press conference.”