Tempe, Ariz. — The Tempe Police Department said Wednesday a "man" who was shot by an officer and later died at a hospital was a 14-year-old boy, reports CBS Phoenix affiliate KPHO-TV.

Police also said he had a replica 1911 model airsoft gun, not a real handgun.

Police said the officer was chasing the teen Tuesday afternoon and at one point, the teen turned around, the officer felt threatened and fired his gun.

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"This is unfortunately a situation that the officer is going to have to live with forever. They're going to carry some issues with them now that they know it wasn't an actual firearm. However, they're doing exactly what they're supposed to do by policy and procedure in their training with the police department," said Kevin Boontjer, a retired police sergeant.

The teen was later found in an alley and taken to the hospital.

Tempe, Arizona police officer stands over airsoft gun authorities say another officer mistook for an actual firearm on January 15, 2019; the officer shot and killed the person carrying the firearm, who turned out to be a 14-year-old boy, during a foot chase KPHO-TV

Police said it all started when they received a call about a suspicious vehicle just after 2:30 p.m. and the officer who arrived found the teen burglarizing the vehicle.

The teen then got out of the vehicle and ran off with the airsoft gun and other items.

During the chase, the officer perceived a threat and shot the teen.

Police said the incident was recorded on the officer's body camera.

"It really doesn't change the dynamics of the event from the officer's perspective unfortunately. It is impossible to train someone on what is a real weapon and a fake weapon. It's just impossible," Boontjer explained.

Boontjer said airsoft guns typically have an orange tip to indicate they're not real firearms. However, he said, some people remove the orange tip, or it can be hard for an officer to see during a chase.

"Let's say that the gun did have the orange tip on it. You're running, your vision is bouncing, you can't keep normal vision as you're running, and you're trying to, again, assess a hundred different pieces of information as you're running," Boontjer explained. "And when we train these officers for these lethal force situations, we can't teach them to look at something so microscopic as an orange dot that is bouncing around, that could be facing away from them as the suspect is running away."

Police said the officer told the teen to stop.

"I would suspect that when this started to occur, the police officer said 'stop' or 'don't run' or something and unfortunately, if the suspect had stopped and followed the orders the officer gave that person, there would probably be a much different outcome," Boontjer said.

An investigation was ongoing.