Shane Tamura, who drove cross-country from Las Vegas and opened fire at the New York headquarters of the NFL, killing four, had CTE, the New York City Office of the Chief Medical Examiner said Friday, confirming what was in the shooter’s own writings.

Police found a three-page note in Tamura’s pocket claiming he had a traumatic brain injury and blaming the NFL for "concealing the dangers to players’ brains to maximize profits."  

Elsewhere, Tamura wrote, "Study my brain please. I'm sorry."

Four people were killed in the shooting: a security guard for the building; an executive at Blackstone who was a wife and mom; a police officer who was a dad of two; and a young employee at Rudin Management.

Tamura died of a self-inflicted gunshot wound.

This is a developing story. Please check back for updates.