A medical examiner has confirmed that Shane Tamura, who killed four people in a Manhattan office tower this summer, was suffering from chronic traumatic encephalopathy. Tamura, a Las Vegas casino worker, shot himself in the chest after the July 28 shooting in a building housing NFL headquarters. The victims included a police officer, a security guard and two office workers. He accused the NFL of hiding evidence of brain injuries. A note found in Tamura's wallet revealed his self-diagnosis and urged the study of his brain. Tamura played high school football in California a decade ago but never played in the NFL.

Police say a gunman who killed four people in a Manhattan skyscraper before taking his own life claimed to have a brain disease linked to contact sports and was trying to target the National Football League's headquarters in the building. New York City Mayor Eric Adams says investigators believe the gunman wanted to get up to the NFL's offices on Monday but entered the wrong elevator. Police say Shane Tamura, a Las Vegas casino worker, had a note in his wallet that suggested he had a grievance against the NFL and asked that his brain be studied. He played high school football in California but never played in the NFL. Among those killed was an off-duty police officer working security.