The man suspected of shooting dead four people midtown Manhattan last month had years earlier threatened to kill himself as he dealt with depression and concussion symptoms, according to a phone call his mother made to police.

On the afternoon of Sept. 12, 2022, Shane Tamura was inside a Las Vegas motel room suffering from a mental health crisis and threatening suicide, his mother told a 911 dispatcher. “He’s under doctor’s care for depression, concussion — like sports concussions — chronic migraine and insomnia,” she said.

The call was one of several 911 calls, documents and body camera videos released Tuesday by the Las Vegas Metropolitan Police Department regarding Tamura, who officials have said had a history of mental health issues and encounters with law enforcement.

Authorities have said Tamura, 27, was trying to target the corporate offices of the National Football League when he walked into a high-rise on Park Avenue late last month and opened fire.

He killed 36-year-old New York Police Officer Didarul Islam, who was working-off duty as a security guard; security officer Aland Etienne, 46; Blackstone employee Wesley LePatner, 43; and Julia Hyman, an employee at a real estate company.

Authorities said Tamura then fatally shot himself in the torso.

Two officials familiar with the case said the former high school football player left a note at the scene repeatedly mentioning “CTE” — thought to mean chronic traumatic encephalopathy, a brain condition caused by injuries to the head.

In the September 2022 call, Tamura’s mother said her son had a concealed carry permit for a handgun, which he kept in a backpack. Tamura had been inside the motel room and begun crying and slamming things, saying his mother’s being there was making the situation worse, she said.

She said she stepped out and was calling from inside her silver Toyota Camry, out of sight of her son. “He didn’t say he made a plan, he just said he just can’t take it anymore,” the mother told the dispatcher.

A Las Vegas metro police officer that day filed an emergency request for Tamura to be admitted to a mental health facility or hospital, according to a copy of the application.

Tamura was bon in Las Vegas and his family eventually ended up in California, where he enrolled in at least two Los Angeles-area high schools.

He started out at Golden Valley High School, in the suburb of Santa Clarita, where he played running back for the football team. A classmate told NBC News that in his junior year, Tamura wasn’t going to be eligible to play due to poor grades. His grades improved, but Tamura didn’t like that he wasn’t going to be the starting running back when he returned, the classmate said.

Tamura then transferred to Granada Hills Charter, where he continued impressing on the football field. It’s unclear if he ever graduated, and he does not appear to have continued playing football after high school.

At some point after high school, Tamura returned to Las Vegas, where he had various documented encounters with police, including for threatening suicide.

Besides the September 2022 call, police were called over Tamura’s threatening suicide at least once more.

In August 2024, someone called 911 about their son, according to a log of the call and police bodycam footage. The caller noted that Tamura previously had a concealed carry permit for a gun, which had since expired, and that he suffered from bipolar disorder, anxiety and depression.

In the video, a police officer arrives to a Las Vegas apartment complex, where paramedics are already in a room with a shirtless Tamura, seemingly checking his vital signs as he sits calmly on a couch.

“He called his mom, made some statements about not wanting to be here anymore, this is it for him,” a paramedic tells the officer. “He’s been calm and cooperative with us, but he did tell us he had a handgun in his bag. But he doesn’t want to go to the hospital.”

The interaction lasts a few minutes and remains calm, with Tamura at one point indicating to the officer where the gun is. After he puts on a shirt and some sandals and grabs a few items, Tamura, the officer and the paramedics step outside and head downstairs, where Tamura gets onto a waiting stretcher and is wheeled out of the apartment complex.

Another emergency application for Tamura to be admitted to a mental health facility or hospital was made that day, a copy of the request shows.

In May of that year, Tamura was also pulled over for driving without a rear license plate, body camera video of the traffic stop shows. He appeared cooperative and was eventually cited for operating an unregistered vehicle and driving without a valid license, according to a copy of the citation, which shows he was released after being cited.

The year prior, though, Tamura had had a more volatile interaction with police at a Las Vegas casino.

According to an arrest report, Tamura had been gambling when security personnel asked him to show his identification, which he refused to do. When asked to leave, he went to collect his winnings but also refused to show identification to claim what he said he was owed — around $5,000 — according to the report.

That’s when security staff called 911. Tamura called 911 as well, according to audio of the call, saying, “They stole my money.” Body camera video shows police and casino staff speaking with Tamura in a room, with one officer growing irate after Tamura repeatedly refused to give his name.

They eventually handcuffed him, took him outside and repeatedly told him to leave, according to the video. When he failed to do so, they handcuffed him again and arrested him, taking him to the Clark County Detention Center.

Tamura’s final interaction with police would be on July 28, when he walked into the high-rise at 345 Park Ave. and opened fire.

Police searched Tamura’s Las Vegas apartment the next day and found a notebook with a goodbye note, prescription pill bottles, an empty gun case, 9 mm rounds, a bipod for a rifle and a rifle cartridge, according to a search warrant. Police said he used a rifle in the killings.

In a note left behind at the scene of the shooting, Tamura accused the NFL of knowingly concealing the dangers to football players’ brains and asked that his brain be studied for CTE.

A spokesperson for the New York City Office of Chief Medical Examiner told NBC News it would examine his brain as part of the autopsy process, which is expected to take multiple weeks.