A gunman, Shane Tamura, killed four people in a Manhattan office building before taking his own life. He claimed in a note to have a brain disease linked to contact sports and intended to target the NFL headquarters but mistakenly took the wrong elevator. Tamura had a history of mental illness and expressed grievances against the NFL regarding chronic traumatic encephalopathy (CTE). The shooting resulted in the death of an off-duty NYPD officer, Didarul Islam, among others. NFL Commissioner Roger Goodell condemned the violence, and investigations revealed Tamura's recent cross-country drive to New York City.