There were 23 shell casings and 13 bullet fragments recovered from the lobby of 345 Park Avenue and 24 spent shell casings on the 33rd floor, police said.

Fear and confusion were rampant after a gunman shot and killed four people and wounded another in a Midtown Manhattan office tower Monday evening before, authorities said, taking his own life.

A New York City police officer who was among the four people shot and killed by a gunman during a rampage at a Manhattan office tower will be laid to rest Thursday. Officer Didarul Islam, 36, was fatally shot Monday in a midtown building housing the National Football League’s headquarters.