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:

Mayor Eric Adams on X: "Tonight, our city is reeling and four innocent families are mourning, including the family of NYPD Officer Didarul Islam, who was killed at 345 Park Avenue. He represented the best of New York City, an immigrant from Bangladesh who put on a uniform to protect and serve us all."