Officer Didarul Islam, 36, who was guarding the building on a paid security job when he was killed, had served as a police officer in New York City for over three years. He was an immigrant from Bangladesh and was working a department-approved building security job when he was shot.

The gunman who killed four people in a New York City shooting Monday was the son of a former Los Angeles Police Department officer, according to a spokesperson for the NYPD. Shane Tamura, 27, of Las Vegas,