The gunman who killed four people in a mass shooting in Midtown in July had chronic traumatic encephalopathy, a brain disease linked to repeated head trauma, city medical examiners announced Friday.

Shane Tamura, 27, had "unambiguous diagnostic evidence" of low-stage CTE, according to the chief medical examiner's office, which completed its neuropathological examination of his brain tissue.

Tamura left a suicide note blaming his mental health struggles on CTE and specifically blaming the NFL for his condition, authorities said. Mayor Eric Adams said at the time that Tamura appeared to be targeting the NFL headquarters in the Park Avenue office building where he opened fire on July 28.

The Las Vegas man killed four people , including NYPD Officer Didarul Islam, before fatally shooting

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