SAN JUAN, Puerto Rico — A federal immigration judge in Miami ordered on Thursday that wealthy Haitian businessman and one-time presidential hopeful Pierre Réginald Boulos remain in custody in the United States, where he is held over accusations of supporting violent gangs in Haiti.

Boulos was arrested at his home in South Florida earlier in July, accused of being “engaged in a campaign of violence and gang support that contributed to Haiti’s destabilization,” the U.S. Immigration and Customs Enforcement has said.

A well-known member of Haiti’s elite, he is the most high-profile Haitian arrested to date under the Trump administration’s immigration crackdown.

Thursday’s hearing at the Krome North Service Processing Center was held behind closed doors, with authorities barring journalists and others from the courtroom and the detention center itself.

It wasn’t immediately known what occurred at the hearing other than the judge denying Boulos be released, a person familiar with the case told The Associated Press. The person spoke on condition of anonymity to discuss the hearing.

More than a dozen people gathered outside the detention center on Thursday, demanding that Boulos remain in the U.S. — or anywhere else but Haiti. The demonstrators waved at cars that passed by and honked in support.

“If Boulos goes to Haiti, he will not stay in prison. The justice in Haiti are gangs,” read one sign.

Some said Boulos should be sent to El Salvador, or even Guantánamo. Another sign read: Send Boulos under the sea.

U.S. authorities have not provided any details on Boulos’s case, and no documents have been made public. Days after his arrest, ICE also said Boulos failed to disclose in his residency application his involvement in the creation of a political party or that Haiti’s government had referred him for prosecution for misusing loans.

It added that the State Department “has determined that certain individuals with U.S. lawful permanent resident status have supported and collaborated with Haitian gang leaders connected to Viv Ansanm, a Haitian foreign terrorist organization.”

“The United States will not allow individuals to enjoy the benefits of legal status in our country while they are facilitating the actions of violent organizations or supporting criminal terrorist organizations abroad,” the statement said.

Boulos ran grocery stores, car dealerships and other businesses while in Haiti, where he served as president of the National Chamber of Commerce and Industry.

Boulos, who was born in the U.S., has previously denied a flurry of corruption allegations in Haiti.

In 2019, he created the Third Way Movement, a political party that he said at the time served as a contrast to the “shameless elite and the unscrupulous politicians who are working to bog down the country and increase the suffering of the people” of Haiti.

Boulos renounced his U.S. citizenship amid expectations of a presidential run, which never materialized. He obtained U.S residency last year, under the Biden administration.