Jon Stewart was among those who saluted the coffin of Luis Alvarez, a former New York City detective who pleaded with Congress this month to extend healthcare to emergency workers who responded to the 9/11 terrorist attacks.

The funeral in Queens, New York, inspired a citywide outpouring of quiet sorrow on Wednesday morning, as hundreds emerged to express their gratitude to a police officer who effectively dedicated his life to public service.

Mr Alvarez died on Saturday from complications of colorectal cancer, a disease diagnosed in 2016 and linked to the three months he spent at the toxic, asbestos-ridden site of the toppled World Trade Center searching for survivors.

The funeral in Astoria came just weeks after he delivered an emotional appeal, sitting alongside Mr Stewart, to lawmakers at a Congressional hearing in Washington to replenish the September 11th Victim Compensation Fund.

Mr Alvarez, the father of three sons, including two teenagers, underscored through his jaundiced and frail appearance alone the stark health problems many first responders continue to suffer nearly two decades on from the attacks.

The appearance before a House Judiciary subcommittee would prove his last act of service after a career as a public servant: he started as a Marine and served in the NYPD Narcotics Division before he was promoted to detective.

Before he went to Washington, Mr Alvarez said: “I will not stand by and watch as my friends with cancer from 9/11 like me are valued less than anyone… I’m going to make sure you never forget to take care of the 9/11 responders.”

He was supported in his bid by Mr Stewart, the former host of the Daily Show, who used his television show to push for federal money for the healthcare of first responders, and attended the funeral alongside Alexandra Ocasio-Cortez.

Jon Stewart (right) speaks to retired NYPD detective and 9/11 responder Luis Alvarez in Congress (Getty)

The efforts of Mr Alvarez and Mr Stewart meant the refunding bill passed the full House committee unanimously. Mitch McConnell, the Republican Senate majority leader, agreed to allow the legislation to go to a floor vote in August.

There is no guarantee the fund, which he supported so passionately and will be depleted in 2020, will make it past the Senate. So far, about 21,000 claimants have received $5bn. Around 19,000 additional claims are pending.

But outside the Immaculate Conception Church in Astoria, the general mood was focused on the present. Silence was the rule, expect for the whirring of helicopters and the snares from the NYPD’s Emerald Society Pipes and Drums.

The casket of Luis Alvarez is carried outside as people attend the funeral mass at the Immaculate Conception Church (Getty)

Mr Stewart elsewhere spoke to Democratic representative Carolyn Maloney, who had also joined Mr Alvarez when he made his heartfelt appeal to Congress. She attended the funeral dressed in a black firefighter’s jacket.