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 in the deadly Midtown Manhattan shooting, Shane Tamura, wrote about the brain disease CTE in a note obtained by investigators.

A Nevada man recently traveled to New York City, entered a Manhattan building wearing body armor, carrying an M4 rifle, and fatally shot four people Monday evening, including a New York Police Department officer and injured another,