Manhattan shooter claims brain disease in suicide note

A former high school football player who opened fire in a Manhattan building Monday — killing four people before fatally shooting himself — left a note seemingly blaming the NFL for giving him a brain disease, investigation reveals.

What happened: The mass shooting began at around 6:30 p.m. at 345 Park Avenue, a 44-story office building that houses the NFL’s headquarters and other major corporations. Shane Devon Tamura, who was wearing body armor and carrying an assault rifle, parked his BMW outside and entered the lobby, where he allegedly opened fire.

Three people were killed on the ground floor, including off-duty NYPD Officer Didarul Islam, building security guard Aland Etienne and Blackstone executive Wesley LePatner. Before taking an elevator, surveillance footage captured Tamura allowing a woman to exit. Seeking to reach NFL offices on the fifth floor, Tamura then mistakenly took the wrong elevator to the 33rd floor Rudin Management offices, where he killed one more person before shooting himself in the chest. A fifth person, an NFL employee, was critically wounded but hospitalized in stable condition.

About the shooter: Tamura, 27, lived in Las Vegas, where he worked in surveillance at the Horseshoe hotel and casino and held a concealed firearms permit. He previously obtained private investigator licenses in California and Nevada in 2019, which both expired.

Ten years ago, he was a standout high school football player. “The sky is the limit with Shane,” Dan Kelley, his Golden Valley High School coach, told the Santa Clarita Valley Signal in 2014. Tamura transferred to Granada Hills Charter for his senior year in 2015 but withdrew after one semester. He also had a documented mental health history, including psychiatric holds in 2022 and 2024, and was arrested for trespassing at a Las Vegas casino in 2023 after refusing to leave when attempting to cash out $5,000. The charges were later dropped.

About CTE: In his suicide note, Tamura appeared to blame the NFL for his alleged chronic traumatic encephalopathy (CTE), a brain disease caused by repeated head injuries that leads to nerve cell death and worsens over time. The condition, however, can only be confirmed after death through brain autopsy and has been identified in football players, boxers and military veterans who experienced head trauma. Symptoms can include cognitive problems, behavioral changes such as aggression and impulsive actions, mood disorders including depression and suicidal thoughts, and movement difficulties.

“Terry Long football gave me CTE and it caused me to drink a gallon of antifreeze,” Tamura wrote in his note, referring to former NFL player Terry Long who died by suicide after drinking antifreeze in 2005 following his CTE diagnosis. “You can’t go against the NFL, they’ll squash you,” he added. The note also asked for his brain to be studied for the disease.

What authorities are saying: Mayor Eric Adams told CBS Tamura “appeared to have blamed the NFL for his injury” despite never playing professionally. He expressed frustration that Tamura obtained a concealed carry permit despite his mental health history, noting that while New York has strong gun laws, “many of our neighboring states have lax gun laws.” Police Commissioner Jessica Tisch said the rifle was assembled by Tamura “using a lower receiver purchased by an associate” and that authorities have located that person and others. Meanwhile, NFL Commissioner Roger Goodell told employees to work from home Tuesday while the building remained a crime scene, adding that the league was “deeply grateful to the law enforcement officers who responded to this threat quickly and decisively.”

The NYPD is reportedly sending two investigative teams to Las Vegas to execute search warrants and examine evidence recovered from Tamura’s background.