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 shooting at a midtown Manhattan office building on Monday left at least five people dead, including an off-duty New York City police officer, sources told The .

Gun laws in the city have largely prevented the sort of mass slaughter common in the rest of America. The last killing of this scale in the city was at a fast-food restaurant in Queens in 2000.

A note written by the shooting suspect was found at the midtown Manhattan office building scene where he killed four people, including an NYPD officer, and himself a day ago, officials familiar with the investigation said overnight.

Barriers were erected in front of the ritzy Midtown Manhattan office building where a crazed gunman killed four people Monday, with access being restricted even to some who work there.

Work was winding down at 345 Park Avenue on Monday when a man strode across the public plaza just outside the Midtown Manhattan tower with an assault rifle in his hand.