Luis Alvarez, the retired police officer who along with Jon Stewart appeared before Congress earlier this month to plead for consistent health benefits for 9/11 first responders, has died.

The Ray Pfeifer Foundation, a nonprofit that helps first responders who became ill after 9/11 with medical needs not covered by insurance, shared the news on social media Saturday morning.

"We lost another 9/11 first responder. Our thoughts are with the family and friends of NYPD Detective Luis Alvarez," the organization wrote on Twitter.

Alvarez was 53 and is survived by his wife and three sons, ages 14, 19 and 29.

The family shared a statement, calling people to "please remember his words, 'Please take care of yourselves and each other."

We lost another 9/11 first responder. Our thoughts are with the family and friends of NYPD Detective Luis Alvarez. pic.twitter.com/rnbhYuFNGJ — RayPfeiferFoundation (@RayPfeiferFDTN) June 29, 2019

Alvarez along with Jon Stewart testified on June 11 at a House Judiciary Committee hearing to make sure a fund to compensate victims of the 9/11 terrorist attacks doesn't run out of money.

"You all said you would never forget. Well, I'm here to make sure that you don't," Alvarez told Congress.

Stewart called out lawmakers who failed to attend the hearing to discuss a bill that would ensure that the September 11th Victim Compensation Fund can pay benefits for the next 70 years.

"Your indifference cost these men and women their most valuable commodity — time. It's the one thing they're running out of," the former "Daily Show" host said.

Shortly after the hearing, Alvarez was placed in hospice care because there is "nothing else the doctors can do to fight the cancer," he said in a Facebook post on June 19.

Even in his final days, Alvarez continued to urge lawmakers to reauthorize the 9/11 victims' fund.

"That's my ultimate goal, legacy, to have this bill passed so first responders have the coverage they need," Alvarez told NBC New York. "I can still work from my bedside, I can still put the word out."

The former NYPD detective had been fighting colorectal cancer since 2016, his son had told the New York Daily News.

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First responders breathed in pulverized dust that included many toxic elements after the towers collapsed. Some of these include cement, asbestos, lead, glass fibers, dioxins and other chemicals.

Alvarez's cancer was among many such cases linked to the aftermath of the 9/11 attacks, according CDC's World Trade Center Health Program.