A gunman who killed four people at a Manhattan office building bought the rifle from his supervisor at a Las Vegas casino, authorities said.

New York City police detectives searched a studio apartment in Las Vegas that belonged to the suspected gunman in Monday's mass shooting at a Midtown Manhattan.

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