A black man reportedly acting erratically at a strip mall in suburban San Diego was shot and killed by El Cajon police a minute after they arrived on scene, authorities confirmed to NBC 7 San Diego. Police say the man pulled an object from his pocket, pointing it at officers and assuming a "shooting stance."

The man, 38, identified as Alfred Olango, was first reported to be walking in and out of traffic in the middle of the street and “not acting like himself,” when a woman police believe may be the man’s sister called officers for help just after 1 p.m. Tuesday.

El Cajon Police Department Lt. Rob Ransweiler said two officers first arrived at the scene at approximately 2:10 p.m. Tuesday. The officer-involved shooting happened at 2:11 to 2:12 p.m., between one to two minutes after they arrived.

El Cajon Police Chief Jeff Davis said that when officers arrived on scene and located Olango, he “refused multiple instructions by the first officer on the scene,” and put his hands in his pants pocket. When officers arrived on scene, they were not aware of Olango's criminal history, as far as he knows, said Ransweiler.

At the time, there was a Psychiatric Emergency Response Team (PERT) in the area, but they were responding to another call of a reported man darting in and out of traffic.

He allegedly pulled an object and held it out “like he would be firing a gun,” Davis said during a press conference on Tuesday night. Police identified the object as a vape device.

El Cajon Police Department

"At one point the male rapidly drew an object from his front pants pocket, placed both hands together on it, and extended it rapidly toward the officer taking what appeared to be a shooting stance putting the object in the officer's face,” Davis said.

The second officer on scene began to immediately prepare a less lethal electronic control device, or Taser, as the first officer covered him, Davis said.

[G] Police Shoot 'Erratic' Man in El Cajon Parking Lot

The officer deployed his Taser to try and subdue the subject, Davis said, though it is unclear whether the Taser struck the man. Davis said that aspect of the incident is under investigation. At the same time, the other officer fired his weapon. It is unclear how many shots were fired.

A Facebook live video shows the aftermath of an officer-involved shooting in El Cajon. A witness shares what she saw with officers at the scene.

Davis said there was also no indication that Olango was suffering an epileptic seizure during the encounter. Officers gave initial first aid to Olango before paramedics arrived and the man was then transported to an area hospital.

Shortly after the shooting, a witness came forward and told officers she had video footage of the incident, Davis said. The witness “voluntarily provided” the cell phone video to the department and gave written consent for officers to use it.

“This was the only cell phone video provided to the officers and no cell phones were taken from anybody,” Davis said. He added that video from the scene coincides with the officers’ statements.

Officers with the El Cajon Police Department are not currently outfitted with body-worn cameras.

NBC 7’s Ashley Matthews is at the scene where a crowd has formed in prayer, sending a message of peace.

Following the incident, witnesses questioned the police motives in the shooting. Crowds gathering by the scene of the shooting began chanting, demanding answers from police.

The protest was angry but peaceful. Several dozen people, most of them black, gathered and some cursed at officers guarding the scene, The Associated Press reported. They chanted "black lives matter!" and "hands up, don't shoot!"

Davis urged the community to remain calm and said the investigation will be thorough.

"This will be transparent," he said. "This will be looked at by multiple sets of eyes, and not just ours."

The district attorney was on scene and also will investigate.

During the press conference, Davis also urged the community to cooperate with the investigation and come forward if they have any information.

"I would like to convey my sincerest appreciation to the community of El Cajon for the strength that they have shown in light of this tragic event," he said.

The woman they believe may be Olango's sister on scene has not cooperated with investigators, Davis said.

NBC 7’s Mari Payton has more on video footage taken at the scene.

“As you can understand, she was upset; she was not cooperating with us,” Davis said. “We can’t even confirm that it was his sister.”

That woman is believed to have called the police to report the initial incident early Tuesday afternoon, Davis said. He added it took officers at least 50 minutes to arrive on scene after the first call.

El Cajon police are asking for the woman come forward, as she may have information they are looking for.

Davis said that the two officers involved in the shooting, who have not been identified, both have more than 21 years of service as police officers.

Both officers have been placed on administration leave.

The entire shooting was captured on cell phone video, but the video will not be released yet as it is part of an ongoing investigation, Davis said. The video will be released in full at a later date, he said.

Meantime, other videos quickly surfaced showing the aftermath, according to the AP. In one posted to Facebook, an unidentified woman is heard telling police at the scene that the man was ordered to take his hand out of his pocket.

"I said: 'Take your hand out your pocket, baby, or they're going to shoot you.' He said 'no, no, no,' " the woman said. "When he lifted his hand out ... he did have something in his hand but it wasn't no gun, and that's when they shot him."

Lucy Peterson, who was wearing hospital-style work clothing, said she's Olango's sister. She appeared distraught, repeatedly shrieking and crying, telling officers that she had called them to help her brother, who she described as mentally ill.

"I just called for help, and you came and killed him," she said.

Olango was born in Uganda and emigrated to the U.S. in 1991 when he was 12 years old, NBC 7 has learned.

Michael Ray Rodriguez was among the witnesses who said the man had his hands in the air. He said that he was driving out of his apartment complex past the shooting scene and saw a shirtless black man with his hands raised.

The officer "let go of the trigger and shot him again and again," Rodriguez told the San Diego Union-Tribune.

NBC 7 speaks to the spokesperson for the El Cajon Police Department following an officer-involved shooting near a Mexican restaurant on Broadway.

The shooting in the community east of San Diego occurred just three days after police in Charlotte, North Carolina, released video showing the Sept. 20 killing of Keith Lamont Scott. In Tulsa, Oklahoma, a police officer shot and killed 40-year-old Terence Crutcher on a highway six days after the Charlotte shooting. In that case, Officer Betty Shelby, has been charged with manslaughter.

Both shootings have reignited protests questioning the actions of law enforcement officers in cases where encounters ended with African Americans being fatally shot.

El Cajon City council members approved the purchase of 88 body cameras this past May, but Davis said he was hoping to have the cameras in use by the start of 2017.

Pastor Miles McPherson of Rock Church followed Davis in the press conference and urged members in the community to pray, and to remain peaceful while the facts continue to unfold.

“We want the truth to come out and the right things to happen, no matter what that means, and we want God to be honored in the process,” Rock Church Pastor Miles McPherson said.

El Cajon, which is about 15 miles northeast of San Diego, has a population of about 100,000. It is 69 percent white and 6 percent black, according to 2010 census figures, and has become a home for many refugees fleeing Iraq and, more recently, Syria.