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.

Didarul Islam, a 36-year-old NYPD officer, was off duty and working a security job when he was fatally shot by a gunman who opened fire at the 345 Park Avenue office building on Monday. Islam, a Bangladeshi immigrant who joined the NYPD four years ago, is survived by his wife, who is eight months pregnant, and two young sons.

Thousands of familly, friends and colleagues are expected to gather to mourn the NYPD officer killed in this week’s Manhattan office attack at a funeral on Thursday, a day after another grieving family laid their loved one to rest,