Family, friends and members of the New York City Police Department will come together on Thursday for a funeral for the "hero" officer who was one of four people killed in the Midtown Manhattan mass shooting.

Officials said the gunman fatally shot himself after his attack, which set off a chaotic scene that rippled out into the heart of Manhattan during rush hour.

Four people were shot and killed in Midtown Manhattan on Monday. The deceased included two males, one female, and one NYPD officer. One male was also shot and is still in critical condition. The shooter died of an apparent self-inflicted gunshot wound, the mayor said.