Police say a gunman who killed four people in a Manhattan skyscraper before taking his own life claimed to have a brain disease linked to contact sports and was trying to target the National Football League’s headquarters in the building.

National Football League commissioner Roger Goodell said one employee was shot and "seriously injured" in a shooting at a midtown Manhattan office building.

Shane Devon Tamura fatally shot four people, including an NYPD officer, in midtown Manhattan before killing himself, officials said.