The Biden administration has paused a migrant sponsorship policy it set up to discourage illegal crossings along the U.S.-Mexico border due to concerns about fraud among sponsors, officials said Friday.

The policy allows up to 30,000 migrants from Cuba, Haiti, Nicaragua and Venezuela to fly to the U.S. legally each month if American sponsors agree to support them financially. The administration first started the program in late 2022 and expanded it in early 2023 to dissuade migrants from those crisis-stricken countries from traveling to the U.S. southern border.

The Department of Homeland Security said it stopped issuing travel documents to people applying for the program while it investigates applications filed by U.S.-based sponsors. 

“Out of an abundance of caution, DHS has temporarily paused the issuance of advanced travel authorizations for new beneficiaries while it undertakes a review of supporter applications,” the department said in a statement Friday. “DHS will restart application processing as quickly as possible, with appropriate safeguards.”

Fox News first reported DHS’ decision to halt travel permits under the program.

DHS first stopped granting travel authorization to Venezuelans under the policy, known as CHNV, in July and then extended the pause to the other three nationalities, two people familiar with the internal steps told CBS News.

The pause, the sources added, was triggered by concerns raised by the fraud detection branch of U.S. Citizenship and Immigration Services, which noted a significant number of would-be sponsors were applying to sponsor multiple migrants.

The fraud concerns being investigated relate to the people in the U.S. applying to sponsor migrants, not the migrants themselves, the sources said. Public reports have suggested that some people have been advertising sponsorships online. Would-be sponsors need to be American citizens, residents or otherwise have a legal status in the U.S.

In its statement, DHS said it refers instances of immigration fraud to the Justice Department for potential criminal prosecution. It also stressed it has not “identified issues” around the vetting of migrants who are eligible for the sponsorship initiative.

Tennessee Rep. Mark Greene, the Republican chair of the House Homeland Security Committee, said the program’s pause “vindicates” his concerns about it.

“This is exactly what happens when you create an unlawful mass-parole program in order to spare your administration the political embarrassment and bad optics of overrun borders,” Greene said in a statement. “The Biden-Harris administration should terminate the CHNV program immediately.”

Since its inception, the CHNV policy has allowed more than half a million Cubans, Haitians, Nicaraguans and Venezuelans to fly to U.S. airports after rounds of security vetting, according to government data.

While arrivals of migrants from Cuba, Haiti, Nicaragua and Venezuela to the U.S. southern border reached record highs in past years, they dropped dramatically after the Biden administration created policies specific to those nationalities. The administration has paired the CHNV program with a policy of returning migrants from these countries to Mexico if they enter the U.S. illegally.

Republican-led states have challenged the CHNV initiative in federal court, arguing it violates the intent of the humanitarian parole law that the Biden administration has invoked to admit migrants under the program. Earlier this year, a federal judge in Texas dismissed the red states’ lawsuit, ruling that they had not been harmed by the policy. The states are appealing that decision.

Migrant crossings at the U.S.-Mexico border soared to record levels in 2022 and 2023. But they have plunged this year, reaching the lowest level in nearly four years in July. Officials have attributed the massive drop to a crackdown on asylum by President Biden, scorching summer temperatures and efforts by Mexico to stop migrants.

Camilo Montoya-Galvez

Camilo Montoya-Galvez is the immigration reporter at CBS News. Based in Washington, he covers immigration policy and politics.