In a press conference Wednesday, Adams said the officer was being chased by Munoz, who was armed with a knife. The officer “ran for his life,” she said, before turning and firing at him.
“There was no time or opportunity for de-escalation,” she said.
The incident began when a woman who identified herself as Munoz’s sister called police at 4:13 p.m. and said he was becoming aggressive with his mother and attempting to break into her house, Adams said. The woman tells the dispatcher that her mother “needs help with you bringing him (Munoz) to the hospital or something.”
“Her son is being very aggressive and he needs help,” the caller says. “He has mental problems.”
The responding officer arrived to the scene and turned on his body camera, which captured the incident.
Body camera footage played at the press conference shows Munoz suddenly appear at the door and run at the officer while wielding a knife. They were within 4 to 7 feet of each other when the officer fired, the investigation found.
The officer then called emergency medical services (EMS) within a minute of the shooting and rendered aid to Munoz, according to Adams. Other officers who arrived to the scene also attempted to render aid but determined that he was “beyond help” and canceled a request for EMS minutes after the shooting.
Officer will not be identified
Adams said she will not release the officer’s name because the shooting was justified. She said she saw “nothing unreasonable” about the officer’s approach.
“I want to recognize that whenever a police officer uses deadly force it is a traumatic and emotionally charged event in our community,” Adams said.
“Certainly for the families directly impacted, for the neighborhood, for the entire police community and for the officer involved. An officer-involved shooting is the most traumatic event an officer will encounter during service, and our thoughts are with this officer as he continues to cope with the events of September 13.”
CNN has reached out to Munoz’s family for comment.
Lt. Bill Hickey, a spokesman for the Lancaster Police Department, told CNN said the city was not releasing the name of the officer or his status at this time and that there was still an ongoing internal department investigation into the incident.
Lancaster Mayor Danene Sorace said in a statement that the police department will now complete its internal investigation about whether any police policies were violated.
“We know the DA’s findings will not satisfy everyone in our community, yet the District Attorney was very clear. My hope is that we can work collectively to prevent a similar tragedy from occurring again,” Sorace said.
She said that shortly after the shooting, mental health providers put together a guide with information about available mental health resources that will be published online and distributed to every household in the city.
Lancaster police said they arrested eight individuals at the time after demonstrators caused damage to the police station, a parked vehicle, and a US Post Office building. Demonstrators also piled street signs, trash cans and other items into an intersection, at one point starting a dumpster fire, according to police.
Those arrested received charges including arson, institutional vandalism, riot, failure to disperse and obstructing highways and other public passages, police said.
CNN’s Mirna Alsharif and Ray Sanchez contributed to this report.