Shane Devon Tamura, the man identified as the gunman who killed four people in a deadly shooting at a midtown Manhattan office building that houses the NFL 's headquarters, was once a standout high school football player.

What we know about Tamura’s life, how he got the assault rifle that he used to kill an NYPD officer and three others, and the timeline of the shooting, which ended with Tamura firing a fatal

Cops identified a man who sold the weapon to mass shooter Shane Tamura as his former supervisor in the Las Vegas area.