Multiple casualties as gunman opened fire in the lobby of the midtown Manhattan building on Park Avenue that is home to the Blackstone investment firm and other corporations before moving to other floors.

A New York police officer, a “beloved” security guard and a senior executive with investment firm Blackstone were among four people killed Monday when a lone gunman stormed a sprawling office tower in Midtown Manhattan and opened fire.

Police say four people, including an NYPD officer, were shot and killed and another was hurt when a man started shooting inside a midtown Manhattan office building.