A 27-year-old suspect in the Manhattan office building shooting that left four dead reportedly carried a note referencing the NFL and claiming to have Chronic Traumatic Encephalopathy (CTE), according to police sources speaking to ABC News. The note's specific contents and its connection to the shooting remain under investigation. CTE is a degenerative brain disease often linked to repeated head trauma, commonly found in athletes, particularly football players. The suspect's mental state and the role of the alleged CTE in the incident are key aspects of the ongoing investigation.