(LEGAFI) -- Citigroup, Inc. has agreed to pay $158.3 million to settle whistleblower lawsuit allegations that it defrauded the government into insuring thousands of risky home loans made by its CitiMortgage unit. 

The Citigroup whistleblower settlement resolves U.S. civil claims brought under the federal False Claims Act against the bank, the third-largest U.S. bank. The investigation was prompted by charges brought against the bank by whistleblower Sherry Hunt, a CitiMortgage employee in Missouri.

The government accused Citigroup of falsely certifying that many of its loans qualified for insurance from the Federal Housing Agency, which is part of the U.S. Department of Housing and Urban Development.

According to whistleblower settlement documents, CitiMortgage "admits, acknowledges and accepts responsibility" for misleading the government into insuring risky home loans. Investigators said the misconduct lasted for more than six years, and that more than 30 percent of the nearly 30,000 HUD-insured mortgage loans that CitiMortgage made or underwrote since 2004 have defaulted, costing the agency nearly $200 million in insurance claims.

The CitiMortgage whistleblower lawsuit is part of a crackdown by the Department of Justice to prosecute lenders it believes contributed to the housing crisis by originating risky loans that should not have been made, insured or sold.

The $158.3 million whistleblower settlement is separate from Citigroup's agreement to pay as much as $2.22 billion under the roughly $25 billion U.S. settlement reached earlier this month with the five major mortgage servicers over alleged foreclosure abuses.