New York shooter's handwritten 'suicide note' explains why he attacked Manhattan NFL offices

A gunman who fatally shot an NYPD officer and three others in a Midtown Manhattan office building on Monday evening left behind a note suggesting his actions were linked to a possible battle with chronic traumatic encephalopathy (CTE), according to law enforcement sources.

A police officer and at least four other people were shot and killed — and several others injured — by Shane Tamura.

The crazed gunman, 27, reportedly referenced the NFL in the multi-page note, which was discovered after he turned the gun on himself on the 33rd floor of 345 Park Avenue - a luxury office tower that houses the NFL’s headquarters on the fifth to eighth floors.

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In the note, it said he suffered from CTE - a brain disease linked to repeated head trauma, a source with knowledge of the investigation told CNN. He also asked for his brain to be studied.

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

He continued in the note: “CTE chronic traumatic encephalopathy. Study my brain please I’m sorry Tell Rick I’m sorry for everything."

The shooter was also found carrying papers which suggest he had a grievance with the NFL and its handling of CTE, CNN has been told.

After carrying out the shooting, Tamura fatally shot himself in the chest. Authorities said Tamura, who had a known history of mental health issues, opened fire in the building's lobby, injuring a fifth person, believed to be an NFL employee, who survived the attack.

League Commissioner Roger Goodell later confirmed in a letter to staff that one of their own had been "seriously injured" in the incident.

The officer, Didarul Islam, had been with the force since early 2022.

Eric Adams, New York City Mayor, paid tribute to Mr Islam at a press conference, describing the horror as "despicable".

He said his thoughts are with the families of those affected.

"This never gets easy," he said.

Mr Islam, a 36 year old father of two, was an immigrant from Bangladesh according to the mayor. Mr Adams identified him as "Officer Islam", and called him a "true blue New Yorker". He says he met the family of the murdered officer, and "I told them he's a hero".

Tamura is believed to have travelled more than 2,500 miles from Las Vegas to New York to carry out the horror on Monday night.

He had previously worked as a security guard at a Las Vegas casino. In his teens, he was a promising high school football player in California.

A former classmate, Caleb Clarke, told NBC News, “It looked like the sky was the limit, and then it wasn’t anymore.”

Tamura graduated from Golden Valley High School in 2016, where he had been a standout running back. His coach had once told the Los Angeles Times he expected "big things" from Tamura during his senior year.

The investigation is ongoing as authorities work to learn more about Tamura’s background and motive.

The city had recently announced it was on pace to have its fewest people hurt by gunfire than any year in recent decades.

For mental health support, contact the Samaritans on 116 123, email them at jo@samaritans.org or visit samaritans.org to find your nearest branch