No motive has been announced. A suicide note was found expressing grievances with the NFL and saying Tamura suffered from CTE, a source said. Follow for live updates.

A gunman killed a New York City police officer and three other people before taking his own life at a Manhattan office tower on Monday, officials said. Law enforcement officials are working to unravel what took place and why this location may have been targeted in a city that recently announced it was on pace to have its fewest

The NYPD sent detectives to Las Vegas to work with federal law enforcement in the investigation into Monday's deadly shooting inside a Midtown Manhattan office building.