Luis Alvarez, 53, was a retired New York Police Department (NYPD) bomb squad detective who worked at Ground Zero in Manhattan in the wake of the 9/11 attacks. He had been fighting colorectal cancer since 2016, the near-certain result of breathing in toxic dust created by the collapse of the World Trade Center towers. The 9/11 first responder recently appeared before the US Congress to urge Congress to extend benefits to those who responded to the 9/11, 2001 terrorist attack in New York.