(CNN) New York Mayor Bill de Blasio gave the key to the city to the family of Luis Alvarez, a 9/11 first responder and activist who died in late June from a 9/11-related illness.

Alvarez, who was 53 when he died, was a retired New York police bomb squad detective who developed cancer linked to the time he spent with other first responders at ground zero.

The mayor said thanked Alvarez's family for his service and said his love and ability to "show up" for others helped so many people.

"To the entire family, you shared Lou with this city," de Blasio said . "You shared him in a way that we will never forget. He made this a better place."

De Blasio presented the key to the city to Alvarez's family.

Among those honoring Alvarez was his brother, Phil Alvarez, activist John Feal and comedian Jon Stewart.

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