Authorities released body camera footage and 911 audio involving Walter Wallace Jr., a Black man fatally shot by officers during what his relatives said was a mental health crisis in Philadelphia last week.

It marks the first time in the Philadelphia Police Department’s history that it has released body camera footage of an officer-involved shooting, Commissioner Danielle Outlaw said at a press briefing Wednesday.

“This is not a milestone to be celebrated,” Outlaw said. “I truly believe that this is an important step in our commitment to transparency.”

Philadelphia Mayor Jim Kenney warned that the footage contained “graphic and violent images,” and may be “intense and traumatic” to watch.

“Transparency is necessary in making meaningful changes in our city, and to keep our offices, institutions and departments accountable,” he said.

The 11-minute video features body camera footage from the two officers involved in the Oct. 26 incident. It shows the officers’ arrival on the scene and the interactions “that led to the shooting itself,” Outlaw said. It also includes audio from several 911 calls preceding the shooting.

At the request of Wallace’s family, only certain footage was released, Philadelphia District Attorney Larry Krasner said.

“We have done here exactly what they asked us to do, to be transparent but also to protect their privacy in a moment of tragedy that has devastated this family,” Krasner said.

In one of the 911 calls, the caller requests that officers respond and says her brother is “over there hitting my mother and father.” Another call from a neighbor reports fighting.

In the body camera footage, an officer can be heard shouting, “Put the knife down now,” multiple times as Wallace emerges from a residence holding a knife and walks onto the sidewalk and street. The officer yells to his mother to “back up” as she approaches Wallace in the street.

Wallace circles around a parked car and follows the officers as they backpedal into the middle of the street with their guns drawn while continuing to order him to put down the knife. Wallace is walking toward the officers when they unleash a barrage of 14 shots, hitting him several times as his mother screams. His family surrounds Wallace as he lays on the street. “We gotta get him to the hospital,” one of the officers says.

Less than a minute passes from the time Wallace leaves the apartment and is shot.

After reviewing the footage last week, the lawyer for Wallace’s family, Shaka Johnson, told reporters he heard one of the offers say “shoot him” before they discharge their firearms.

The commissioner identified the two officers involved in the shooting on Wednesday as Sean Matarazzo, 25, who has been with the department since 2018, and Thomas Munz, 26, who has been with the department since 2017.

The district attorney’s office and the police department’s internal affairs unit are currently investigating the shooting. They will work together to determine whether the officers will be criminally charged, Outlaw said.

The officers have been placed on desk duty pending the outcome of the investigation.

In the wake of the fatal shooting, city officials announced several reforms on Wednesday, including Project ABLE (Active Bystandership for Law Enforcement) training to help prepare officers to intervene to prevent harm, and courses for 911 dispatchers to better identify crisis-related calls.

Wallace’s mother, Cathy Wallace, said last week police were called to her home three times on Oct. 26, but were not able to help her and her family deal with the mental health emergency her son was experiencing. She said that when officers returned to her home the third time, they ended up shooting her son multiple times when he broke free of her and appeared to step toward two officers with a knife.

“I was telling the police to stop, ‘Don’t shoot my son, please, don’t shoot my son,'” Cathy Wallace said at a news conference. “They paid me no mind and they just shot him.”

The two officers involved in the shooting did not have less-lethal tools, like stun guns, due to a department-wide lack of resources, Outlaw said following the shooting.

The killing of Wallace and graphic cellphone video of the deadly encounter sparked protests as well as rioting and looting in Philadelphia. Unrest in the city resulted in more than 200 arrests and 57 officers injured, Philadelphia ABC station WPVI reported.

Officials and community leaders urged people to refrain from violence on Wednesday.

“We must honor the memory of Walter Wallace. Do not be chaotic and destroy,” Mark Tyler, pastor of Mother Bethel African Methodist Episcopal Church in Philadelphia, said. “Be calm to allow the system to do what the system has promised to do. Do not take matters into your own hands.”

ABC News’ Bill Hutchinson contributed to this report.