The suspect killed four people inside a Manhattan office building Monday and likely sought to target the headquarters of the National Football League.

President Donald Trump expresses support for law enforcement after a Manhattan office shooting that killed NYPD Officer Didarul Islam and three others.

Here's how NFL players, coaches and executives reacted to a mass shooting at the league's office building in Manhattan:

The New York City office building at 345 Park Avenue where a deadly shooting occurred serves is the headquarters of investment firm Blackstone, as well as the NFL and Rudin Management.

A New York police officer, a “beloved” security guard, a young Cornell graduate and a senior executive with investment firm Blackstone were killed Monday when a lone gunman stormed a sprawling office tower in Midtown Manhattan and opened fire.

Rep. Nicole Malliotakis spoke with Fox News Digital after the deadly shooting that left multiple people including a police officer dead.

The police officer who was killed when a gunman opened fire in a Manhattan building was a dedicated father who was working a second job as a security guard.