A shooting at a midtown Manhattan office building on Monday left at least five people dead, including an off-duty New York City police officer, officials said.

A 27-year-old man wearing body armor and carrying an M4 assault rifle shot and killed four people, including an off-duty police officer working security in a Midtown Manhattan office building, officials said during a press conference Monday evening. A fifth victim was left critically injured in the shooting, officials said.