Police have identified the man who they say entered a Midtown Manhattan office building wearing body armor and opened fire, killing four people with a high-powered rifle, as Shane Devon Tamura.

The gunman, who said in a note he believed he had CTE, targeted skyscraper that houses the NFL's headquarters.

Shane Tamura, a 27-year-old former high school football player from Las Vegas with a documented mental health history, was identified as the gunman who killed four people, including an NYPD officer, in a mass shooting at 345 Park Avenue in Manhattan on July 28,