A former NYPD detective who was fighting for 9/11 funding died overnight.

The Oceanside man was 53 years old.

After 9/11, Luis Alvarez spent weeks at ground zero. He was diagnosed with colorectal cancer in 2016. He was one of thousands of first responders who got sick from the toxic dust after the towers collapsed.

Alvarez had testified before Congress about the need to replenish the 9/11 Victims Compensation Fund

He was in hospice care in Rockville Centre when activists met with Senate Majority Leader Mitch McConnell last week.

The activists gave Sen. McConnell Alvarez's badge.

McConnell has promised to renew the fund. Rep. Peter King (R-Seaford) says it needs to be done with urgency.

"He never gave up, he never made it about himself. Just a tough guy, great American and he was fighting for the victim's compensation fund right to the very end, right up until, literally the day he died," King said.

John Feal, a recovery worker and a longtime activist, says Alvarez was one of his close friends and that the news of his death was “unbearable.”

“Lou is a dear friend. His passing will not be in vain. We will get legislation passed,” Feal told News 12.

The family released a statement that reads, "We told him at the end that he had won this battle by the many lives he had touched."

The family is asking for privacy at this time while funeral arrangements are being made.