Four people were killed and a fifth was injured in a mass shooting at a Midtown Manhattan office building on Monday. The injured victim was an employee at the NFL, according to NFL Commissioner Roger Goodell. Here's what we know about the four people killed:

The four victims who were killed inside a Midtown office building ​on Monday include an NYPD officer, a security guard, a Blackstone employee and a Cornell grad.

An NYPD officer, a Blackstone executive, a Rudin Management associate and a security guard were killed in the shooting at Manhattan's 345 Park Avenue.