NFL HQ shooter: Gunman revealed to have been suffering from 'low-stage' CTE

The gunman who entered the Midtown Manhattan building that houses the NFL’s headquarters in late July, killing four people, has been diagnosed with “low-stage CTE,” according to the New York City chief medical examiner. The NYC OCME revealed the diagnosis following a posthumous neuropathological examination of the brain of the late shooter, 27-year-old Shane Tamura, who committed suicide at the scene.

Tamura entered the Manhattan building at 345 Park Avenue — home of the NFL’s headquarters — on July 28 wearing body armor and carrying an AR-15-style rifle. Once inside, Tamura killed four, including an off-duty New York City police officer working as building security, then barricaded himself inside an office on the 33rd floor before turning the weapon on himself and committing suicide. It was the deadliest mass shooting in New York City since 2000.

Breaking: The NYC Office of the Chief Medical Examiner found that the brain of Shane Tamura, the shooter at NFL HQ this summer, had evidence of “low-stage CTE.” pic.twitter.com/GJmhP0mRgc

— Amanda Christovich (@achristovichh) September 26, 2025

“Following a thorough assessment and extensive analysis by our neuropathology experts, OCME has found unambiguous diagnostic evidence of Chronic Traumatic Encephalopathy, also known as CTE, in the brain tissue of the decedent (Tamura),” the OCME statement read Friday afternoon. “The findings correspond with the classification of low-stage CTE, according to current consensus criteria. CTE may be found in the brains of decedents with a history of repeated exposure to head trauma. The science around this condition continues to evolve, and the physical and mental manifestations of CTE remain under study.”

Investigators initially believed Tamura intended to target the NFL, but never made it to their offices after entering the wrong bank of elevators. NFL employee Craig Clementi, a member of the NFL staff who worked in the finance department, was among several injured in the attack after being struck in the back, according to The Athletic’s Dianna Russini.

Among those killed was NYPD officer Didarul Islam, who was working paid detail at the building at the time of the shooting. Thousands attended his funeral on Thursday in New York City, including NFL commissioner Roger Goodell. He called the loss “tremendous” for the community.

Tamura was reportedly found with a suicide note in his pocket that indicated he believed he suffered from CTE, a neurodegenerative disease connected to repeated hits to the brain, usually in connection to extreme contact sports like football. The note reportedly requested doctors study his brain to confirm the CTE diagnosis. Tamura, originally born in Hawaii, played football through high school in Granada Hills, Calif., outside Los Angeles.