New York City shooter Shane Tamura left his parents an eerie note before he drove from his Las Vegas apartment to the Big Apple in a rampage against the National Football League. 

Tamura, a 27-year-old former high school football star, told his parents he felt like a ‘disappointment’ to them in the letter, according to the New York Post.

‘When I look into you and dad’s eyes, I see complete disappointment,’ it read.

Tamura had grown up in Santa Clarita, north of Los Angeles, the son of an 18-year veteran of the Los Angeles Police Department. 

Records show he had obtained a security guard license from the California Bureau of Security and Investigative Services on March 7, 2019, which expired on March 31, 2021. 

He also had a private investigator license in Nevada, which listed his parents’ house as his residence, issued in December 2019. It expired on December 28.

It said he had a ‘no’ firearm status, meaning he wasn’t legally allowed to carry while on the job, as New York City Police Commissioner Jessica Tisch explained that he had a ‘documented mental health history.’

Yet Tamura was somehow able to obtain a concealed firearms permit from the Las Vegas Metropolitan Police Department – which he had on him when he strolled into the skyscraper at 345 Park Avenue in Midtown Manhattan and killed four people.

He had traveled across the country to conduct the broad daylight attack before he took his own life.

New York City shooter Shane Tamura, 27, was apparently targeting the National Football League when he opened fire on a Midtown Manhattan skyscraper Monday night

He left a note at his Las Vegas home (pictured) for his parents, saying he felt like he was a ‘disappointment’ to them

Despite being unable to carry while working as a private investigator and his reported mental health issues, Tamura was able to obtain a concealed firearms permit from the Las Vegas Metropolitan Police Department, issued on June 14, 2022, that wouldn’t expire until 2027

It now appears that Tamura, who most recently worked as a surveillance department employee at the Horseshoe Las Vegas hotel and casino, blamed the NFL for his mental health issues.

In a three-page note found on Tamura’s body he railed against the league for its handling of the brain disease chronic traumatic encephalopathy, which is strongly linked to sports in which players experience repeated head impacts.

‘Terry Long football gave me CTE and it caused me to drink a gallon of antifreeze,’ Tamura wrote, according to CNN. ‘You can’t go against the NFL, they’ll squash you.’

The shooter was referring to former Pittsburgh Steeler Terry Long, who committed suicide by drinking antifreeze in 2006 after suffering from CTE.

‘Study my brain please I’m sorry Tell Rick I’m sorry for everything,’ the note read.

Police also found medication inside his BMW, which he drove cross-country.

When he finally reached the lobby of the high-rise office building, where the NFL is headquartered, at around 6.30pm on Monday, Tamura opened fire – shooting NYPD Officer Didarul Islam in the back and a security guard who took cover behind a desk.

He then proceeded up to the 33rd floor, the offices of Rudin Management – which runs the building and other offices across the Big Apple – where he shot and killed Rudin employee Julia Hyman.

Blackstone executive Wesley LePatner and security guard Aland Etienne were also killed in the attack.

Tamura stepped into the lobby of the building at 345 Park Avenue and began firing, sending workers frantically running for their lives

Four people were killed in the attack. FDNY firefighters are pictured wheeling a police officer on a gurney as police respond to an incident in the Midtown Manhattan neighborhood on Monday night

Officer Didarul Islam, 36, who was working private security at the time, was one of the victims, as was Julia Hyman, an associate at Rudin on the 33rd floor. Tamura reached that floor via an elevator, which authorities believe wasn’t the one he intended to take

Police now believe was the shooting was premeditated and likely suicidal.

‘It appears that he knew it would be his last stand,’ said CNN chief law enforcement analyst John Miller, a former NYPD deputy commissioner.

‘He fully intended to shoot his way through the lobby and make his way to that target – whatever that might have been.’

It has since been revealed that an associate also sold him gun parts for the assault rifle he used in the attack.

In a video update on Tuesday, Tisch said investigators were heading to Tamura’s Las Vegas home to conduct interviews and execute a search warrant. 

‘The weapon used, an AR-15-style assault rifle, was assembled by Mr. Tamura using a lower receiver purchased by an associate. We have located that associate and others. And will be questioning him about that purchase,’ she said.

Tamura had once been a promising football player in junior varsity, obsessed with the game and once on a path suggesting a future defined by discipline and teamwork. Pictured in 2015

It has since been revealed that an associate sold Tamura parts for the assault rifle he used to carry out the mass shooting (pictured)

Meanwhile, Tamura’s old high school friends said they were stunned to learn the former running back was the mass shooter.

‘You never would have thought violence was something you’d associate with him,’ classmate Caleb Clarke told NBC.

‘Everything he said was a joke.’

His former coach Walter Roby also said Tamura was a talented football player and a ‘quiet kid’.

‘I’m just blown away right now,’ he said.