*

Four people shot dead, including New York police officer

*

Shooter worked security for a casino, suffered mental

illness

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Carnage unfolds in skyscraper housing NFL, financial firms

*

Blackstone executive and Rudin associate among those

killed

(Adds details from police commissioner throughout, victim

identities; updates NFL commissioner memo)

By Lananh Nguyen, Doina Chiacu and Brendan O'Brien

NEW YORK, July 29 (Reuters) - The man who shot four

people dead with an assault-style rifle inside a Midtown

Manhattan skyscraper was carrying a "suicide note" that blamed

the National Football League for a degenerative brain disease he

said he had, New York City's police commissioner said on

Tuesday.

Police have identified the gunman as Shane Tamura, 27, a Las

Vegas casino security officer and former high school football

player with a documented history of mental illness.

Tamura killed two security guards, one of them a city

policeman on security detail, as well as a real estate executive

and a business management associate, before taking his own life

on the 33rd floor of the Park Avenue skyscraper.

An employee of the NFL, which has its headquarters in the

building alongside offices of major financial firms, was gravely

wounded in the attack, which was the deadliest mass shooting in

New York City in a quarter century.

The NFL worker was among several people shot in the lobby

before Tamura, targeting the football league, used the wrong

elevator bank and ended up in the 33rd-floor office suite of

Rudin Management, a real estate company that owns the building,

city officials said.

"A suicide note found in his possession at the scene

spoke to a possible motive in the shooting and may explain why

he targeted NFL headquarters," Police Commissioner Jessica Tisch

said in a video message posted on YouTube on Tuesday.

In the note, Tamura "claimed to be suffering from CTE,

possibly from playing high school football, and he also blamed

the NFL," Tisch said. CTE, or chronic traumatic encephalopathy,

is a degenerative

brain disease

.

'STUDY MY BRAIN'

The note, Tisch said, mentions a 2013 "Frontline"

documentary featuring former NFL players who suffered from CTE,

which has no known treatment and can be caused by repeated

shaking of the brain associated with playing contact sports.

Linked to aggression and dementia, the condition can only be

diagnosed conclusively after death.

"'Study my brain. I'm sorry,'" Tisch quoted Tamura as having

written in the note.

The NFL has paid more than $1 billion to settle

concussion-related lawsuits with thousands of retired players

after the deaths of several high-profile players. It has made

changes to the sport to mitigate the risk of concussions.

Tamura was never an NFL player, but he did play football

during high school in California, according to school sports

databases.

A former coach of Tamura, Walter Roby, told Fox News that

Tamura was a "quiet, hard worker" and one of his "top offensive

players" on the Granada Hills Charter School team.

According to police, the first victim slain on Monday was

Didarul Islam, 36, a New York Police Department officer who

immigrated to the U.S. from Bangladesh and was the father of two

young boys. Islam's wife is pregnant with their third child.

Assigned to the building's security detail, he was hailed by

Mayor Eric Adams as a "true blue" hero.

A private security officer, identified by family as

Aland Etienne, was fatally shot in the lobby moments after

Islam, along with Wesley LePatner, a senior real estate

executive for Blackstone, the private equity firm also

headquartered in the tower. Several of her colleagues at

Blackstone were injured, according to the company.

FEAR AND SHOCK

The last victim killed was Julia Hyman, a 2020 graduate

of the Cornell Nolan School of Hotel Administration, who was

working as an associate at Rudin Management, according to her

alma mater.

The skyscraper was closed to workers on Tuesday, as were

some neighboring buildings, although much of Park Avenue hummed

as usual.

The Park Avenue shooting follows last year's murder of a

UnitedHealth executive outside a hotel located just a few blocks

away. Prosecutors say the man charged with that murder targeted

his victim as a symbol of corporate greed.

NFL Commissioner Roger Goodell wrote in a staff memo that

New York-based league employees should plan to work remotely

through at least the end of next week. An NFL spokesperson did

not respond to queries about the shooter's reported motives.

HISTORY OF MENTAL ILLNESS

Tamura appeared to have driven to Manhattan from Las Vegas

over three days and to have acted alone, Tisch told reporters on

Monday night.

In her video message on Tuesday, the commissioner said

NYPD detectives would be questioning an unnamed "associate" of

Tamura who she said had purchased a component of the

"AR-15-style assault rifle" that he assembled for the killing

spree.

"This is part of a larger effort to trace Mr. Tamura's

steps from Las Vegas to New York City," Tisch said.

Security video circulated by police showed a man walking

from a double-parked car into the Park Avenue tower carrying

what police identified as an M4 Carbine, a large semi-automatic

rifle popular with civilian U.S. gun enthusiasts that is modeled

on a fully automatic rifle used by the U.S. military. In Nevada,

unlike New York, no permit is needed to buy a rifle or carry it

openly in public.

The security camera system flagged the gunman as a potential

threat requiring immediate attention as he walked toward the

building and seconds before he burst into the building's lobby,

according to two former federal officials familiar with such

systems.

A widely circulated photo showed the Nevada permit issued to

Tamura allowing him to legally carry a concealed handgun. He had

recently worked as an overnight security guard at the Horseshoe

Las Vegas hotel-casino, Tisch said.

On two occasions, in 2022 and 2024, records show law

enforcement officials detained Tamura for up to 72 hours under a

"mental health crisis hold," which requires the detainee to be

evaluated at a hospital, ABC News reported.