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.

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 police officer and at least four other people were shot and killed — and several others injured — by a crazed gunman who stormed a swanky Midtown skyscraper early Monday evening — before turning