Senator Susan Collins is backing legislation to recover billions of dollars in pandemic unemployment assistance stolen by fraudsters.

The senator’s office says $164 billion was paid out in fraudulent pandemic unemployment payments, and only about $4 billion of that has been recovered so far.

“The government has an obligation to taxpayers to recover as much of this stolen money as possible,” said Senator Collins. “Our legislation would provide states with the resources to help recover these stolen funds and help prevent future theft of unemployment benefits.”

Collins introduced the Chase COVID Unemployment Fraud Act alongside a group of Republican colleagues. She says it would seek to recover the funds through aggressive identification, investigation, and prosecution of criminal fraud in pandemic unemployment programs.

According to reporting in the New York Times, the federal government has charged 1,500 people with defrauding pandemic aid programs so far, with more than 450 convicted. That as 39,000 investigations by the Labor Department are ongoing.