AUSTIN, Texas — Austin police officers believed they were responding to an armed teenager early Friday morning. Minutes later, the 17-year-old was dead.

Investigators later determined no firearm was found. Instead, police said the teen had a water bottle tucked into his waistband and believe he may have been attempting what they described as a “suicide by police.”

As multiple investigations continue, CBS Austin reviewed newly released body camera footage with a University of Texas sociology researcher who studies police practices to better understand the split-second decisions officers are trained to make during encounters they believe involve a deadly threat.

Austin police said 911 received a call at 3:51 a.m. reporting a young person with what appeared to be a gun in his waistband near a park in the 10100 block of Baden Lane. Officers arrived within minutes and repeatedly told the teen to keep his hands up.

Body camera video released by the department shows the teen lifting his shirt and reaching toward his waistband before three officers opened fire.

PREVIOUS COVERAGE: Unarmed teen fatally shot by Austin officers in suspected ‘suicide by police’

Michael Sierra-Arévalo, a policing researcher and associate professor in the Department of Sociology at the University of Texas at Austin, said the information officers had before arriving on scene is an important part of understanding the encounter.

“I believe the evidence is that this is the person that placed the 911 call, and they seem to have correctly understood that to call officers and tell them someone has a gun and then to motion for their waistband, is likely to lead to officers deploying deadly force.”

Police later determined the 911 call came from the teen’s own phone and said investigators believe he was the caller. Chief Lisa Davis said those findings led investigators to believe the shooting was “potentially a suicide by police.”

Investigators also determined the object in the teen’s waistband was a water bottle, not a firearm.

Davis said officers were forced to make decisions in a rapidly changing situation.

“Officers are often required to make life or death decisions in seconds. This was a rapidly evolving incident.”

During an interview with CBS Austin, Sierra-Arévalo was asked whether officers receive training to recognize situations where someone may be attempting “suicide by police.”

He said officers do receive some instruction on recognizing mental health issues, but said the extent of that training can vary.

“Officers, depending on the level of training that they get and depending on the academy, will receive some training in mental health awareness,” he said. “I think it remains to be seen what sort of training these officers had.”

He added that officers generally receive more training focused on responding to perceived deadly threats.

“They receive far more training on actually just assuming that individuals that they encounter pose a potentially lethal threat.”

Sierra-Arévalo said investigators reviewing the shooting will likely examine more than just the moment officers fired.

“I noted, the officers fired well over a dozen rounds between them in the first salvo, there was a pause, and then more rounds were shot,” he said. “I think what’s going to end up happening here is a question as to whether all of those shots were reasonable.”

Austin police said Officers Jake Pitcher, Alexis Cruz, and Avery Zucchi remain on paid administrative leave, as required by department policy following an officer-involved shooting.

The department said it is conducting both a criminal investigation through its Special Investigations Unit, alongside the Travis County District Attorney’s Office, and an administrative investigation through Internal Affairs with oversight from Austin Police Oversight.

Police have not released the teen’s name as they await positive identification from the Travis County Medical Examiner’s Office.

If you or someone you know is struggling with thoughts of suicide, help is available by calling or texting the 988 Suicide & Crisis Lifeline.