New York City is mourning an NYPD officer and three other people killed in Monday's shooting inside an office building in Midtown Manhattan. Officer Didarul Islam was in uniform working as a security guard for a private company at the time of the shooting,

The police officer who was killed when a gunman opened fire in a Manhattan building was a dedicated father who was working a second job as a security guard.

Didarul Islam, an NYPD officer, was killed by Shane Tamura at 345 Park Avenue in Manhattan, before the assailant turned the gun on himself.