Video above: Can the NFL do more to prevent concussions?

NEW YORK (WPIX/NEXSTAR) — Authorities say Shane Tamura, the man accused of fatally shooting four people in a Manhattan office building before turning the gun on himself on Monday, claimed to suffer from a serious brain disease in a note he left behind.

Mayor Eric Adams said Tamura, 27, apparently had a grievance with the NFL over his own belief that he had suffered CTE. Tamura played high school football in Los Angeles, according to ABC News, but did not play in the NFL, whose headquarters are located in the Midtown skyscraper.

CTE, short for chronic traumatic encephalopathy, is a disease that impacts how the brain functions. According to the Centers for Disease Control and Prevention, CTE has been "linked to a build-up of abnorma

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