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:

A shooting Monday at an office building in New York City that is home to the Blackstone investment firm and the NFL left four people dead, including an NYPD officer.

Blackstone, a global investment firm, mourned the victims in its own statement, in which it remembered LePatner as a "brilliant, passionate, warm, generous, and deeply respected" member of its firm "and beyond" who "embodied the best of Blackstone."