After a gunman opened fire in a New York City office building and killed four people, experts share strategies for workplaces to implement to mitigate acts of violence.

The gunman who killed four people, including an NYPD officer, inside a Manhattan office building Monday evening left a note ...

Authorities say the gunman who opened fire in a Midtown Manhattan office building on Monday night -- killing four people and injuring a fifth -- had a history of mental illness and may have been ...