Congressional leaders and FDNY firefighters gathered for a rally in Manhattan Sunday to help first responders who are dealing with 9/11-related illnesses and cancers.

The event comes before critical vote on the Never Forget The Heroes Act in the U.S. House of Representatives. The act would reauthorize the Victims Compensation Fund to make the funding stream permanent to the families and victims affected by ground zero toxins.

Back in February, the 9/11 Victims Compensation Fund had announced that due to a shortfall, responders would see funding cuts unless Congress acts.

"It's absolutely essential we pass the compensation fund," says Rep. Peter King (R-Seaford). "We thought there was enough money in it, but there's so many new cancers. For instance, just in the fire department alone there's over 3,500 people who have come down with cancers since 9/11, directly related to 9/11. They've lost over 190 firefighters since 9/11 -- they lost 343 that day. And this is going on and on, these are cancers that develop late."

The bill will be introduced on Tuesday, and there will be hearings and a vote to follow.

There is no set dollar amount as to how much is needed to pay for the act.

After 9/11, many first responders were told the air was safe to breathe at ground zero. More than 3,000 people have died from the toxins at ground zero since 9/11.