Authorities say the man who killed four people at a Manhattan office building bought the rifle he used in the attack and the car he drove across country from his supervisor at a Las Vegas casino.

Dramatic photos shared online show the blood-stained assault rifle gunman Shane Tamura used to open fire inside a Midtown Manhattan skyscraper , killing an officer and four others.

Shane Tamura, a 27-year-old private investigator from Las Vegas, has been identified as the gunman behind Monday's Midtown Manhattan shooting.