Investigators plan to question a man who supplied parts for a gun used in the shooting at a Manhattan office building that houses the National Football League’s headquarters

Officials said the gunman fatally shot himself after his attack, which set off a chaotic scene that rippled out into the heart of Manhattan during rush hour.

Four people, including an off-duty NYPD officer, were killed and another person was critically wounded in a shooting Monday at a midtown Manhattan building that houses the NFL offices and some of the country's top financial firms,