The gunman in the deadly shooting at a New York City office tower had a background in casino surveillance and once held a private security guard license.

A gunman from Las Vegas shot five people, killing four, including an off-duty New York City police officer, inside a Manhattan skyscraper, before fatally shooting himself, officials confirmed

In a video message, Tisch said Tamura left a suicide note and claimed to be suffering from chronic traumatic encephalopathy (CTE), possibly from playing high school football. Tamura also blamed the NFL and asked that his brain be studied for signs of the degenerative disease.

Shane Devon Tamura was the 27-year-old man living in Las Vegas who fatally shot at least four people in a mass shooting at 345 Park Avenue in New York City on July 28. Here's what to know about the N.

Police have identified the man who entered a Midtown Manhattan office building wearing body armor and opened fire killing four people with a high-powered rifle, as Shane Devon Tamura.

The residence of Shane Tamura, identified as the gunman in the fatal shooting at a Manhattan office building in New York City and who was killed by a self-inflicted gunshot wound is seen on Monday, July 28, 2025 in Las Vegas, Nev. (AP Photo/Ty O’Neil)

Shane Tamura, who shot and killed four people in a Manhattan office building, once worked surveillance for a Las Vegas casino. In a suicide note, the 27-year-old referenced CTE and claimed the NFL "failed" him.

Tamura was involuntarily held after being considered a danger to himself or others, according to a law-enforcement official.

Investigators found a note left by Midtown mass shooter Shane Tamura at his Nevada apartment saying he felt like a "disappointment" to his parents -- including his father, a retired cop, sources told The Post.

Authorities also found a vehicle with Nevada plates registered to Tamura at the scene, with a rifle case inside, sources said.