While news of the shooting sent shockwaves across the league, the development that the NFL offices were specifically targeted left some deeply stunned.

Follow along for live updates on the New York City shooting, where police investigate motive after five people, including the gunman, were killed in the Monday shooting.

Baltimore Ravens head coach John Harbaugh commented on the shooting that killed four people inside a New York City building that houses the NFL headquarters.

A man exited a double parked BMW with an M4 rifle and then walked toward the skyscraper that is home to the headquarters of both the NFL and Blackstone, one of the world’s largest investment firms, as well as other tenants on Monday evening, according to surveillance video.

The man who killed four people in a rampage with a rifle through a Midtown Manhattan office building was carrying a note that appeared to blame the National Football League for his degenerative brain disease,

Shane Tamura said he had CTE. His claim, which is unproven, has again put a spotlight on the NFL's troubling history with its players and the disease.

The Rudin family, which owns the building and Rudin Management, said in a statement that one of their employees was a victim of the shootings but did not disclose the person’s name at the request of relatives. Police officials said a woman was found dead on the building’s 33rd floor in Rudin’s offices.

NFL Network host Kyle Brandt shared an emotional message after gunman killed four people and injured several others in a New York City building where the NFL headquarters is located.