“Now he’s in an abyss with no one to rescue him,” Ms. Casique said on Sunday in an interview from her home in Venezuela.

The deportation of 238 Venezuelans to El Salvador this weekend has created panic among families who fear that their relatives are among those handed over by the Trump administration to the Salvadoran authorities, apparently without due process.

The men were described by the White House press secretary, Karoline Leavitt, as “terrorists” belonging to the Tren de Aragua gang. She called them “heinous monsters” who had recently been arrested, “saving countless American lives.” But several relatives of men believed to be in the group say their loved ones do not have gang ties.

On Sunday, the Salvadoran government released images of the men being marched into a notorious mega-prison in handcuffs overnight, with their heads newly shaven.

Like other Venezuelan families, Ms. Casique has no proof that her son, Francisco Javier García Casique, is part of the group, which was transferred to El Salvador on Saturday as part of a deal between President Nayib Bukele and the Trump administration. The Salvadoran leader has offered to hold the Venezuelan migrants at the expense of the U.S. government.

However, Ms. Casique said that not only had her son’s name disappeared from the website of U.S. Immigration and Customs Enforcement, she also recognized him in one of the photos of the recently arrived deportees that El Salvador’s government has circulated. When she saw him in the photograph, she said, she felt “broken at the injustice” of what was taking place.

Neither government has made public the names of the Venezuelan deportees, and a spokeswoman for the Salvadoran government did not respond to a request for confirmation that Ms. Casique’s son was part of the group. The U.S. Department of Homeland Security, which oversees Immigration and Customs Enforcement, did not respond to a request to confirm whether Mr. García had been deported to El Salvador, either.

Ms. Casique said she had identified Mr. García by the tattoos on one of his arms, as well as by his build and complexion, though his face was not visible. The photo shows a group of men in white shirts and shorts with shaved heads, their arms restrained behind their backs.

In recent years, Venezuelans have migrated to the United States in record numbers, as their country has spiraled into crisis under the government of Nicolás Maduro. Because Mr. Maduro, unlike most other leaders in the region, has not accepted regular deportation flights from the United States, the Trump administration has been looking for other ways to deport Venezuelans.

On Sunday, Venezuela’s government forcefully denounced the transfer of the migrants to El Salvador, saying in a statement that the United States had used an outdated law — the Alien Enemies Act of 1798 — to carry out an illegal operation that violated both American and international laws.

From the start of his presidential campaign, Mr. Trump has focused on Tren de Aragua and its presence in the United States. When he deported a large group of Venezuelans last month to Guantánamo, a U.S. military base on Cuba, Mr. Trump also said that the deportees belonged to the gang, a claim that some of their relatives have denied.

Neither the United States nor the Salvadoran government has offered evidence that the migrants are connected to Tren de Aragua, a gang that originated in Venezuela’s prisons but whose reach now extends throughout Latin America. Mr. Trump, whose government designated it a terrorist group, has zeroed in on incidents that, he said, show the presence of Tren de Aragua in the United States.

Mr. Bukele said that the deportees would be held for at least a year and made to perform labor and attend workshops under a program called “Zero Idleness.”

Ms. Casique said her son had no gang affiliation and had entered the United States to seek asylum in late 2023, after several years spent working in Peru to support his family back home. During his journey north, he was injured in Mexico when he fell from a train, she said.

Mr. García, who had turned himself over to the authorities at the U.S. border, was detained at a routine appearance before immigration officers last year after they spotted his tattoos, Ms. Casique said.

The tattoos, which she says include a crown with the word “peace” in Spanish and the names of his mother, grandmother and sisters, led the authorities to place Mr. García under investigation and label him as a suspected member of Tren de Aragua, according to Ms. Casique.

Mr. García remained in a detention center in Dallas for two months, his mother said, but a judge ultimately decided that he did not pose a danger and allowed him to be released as long as he wore an electronic device to track his movements.

The New York Times could not independently verify why he had been held and released.

After Mr. Trump’s inauguration this year, Mr. García became worried, but Ms. Casique remembered telling her son that he had nothing to fear: The administration said it would go after criminals first.

But on Feb. 6, the authorities arrived at Mr. García’s door and took him into custody.

“I told him to follow the country’s rules, that he wasn’t a criminal, and at most, they would deport him,” Ms. Casique said. “But I was very naïve — I thought the laws would protect him.”

Gabriel Labrador contributed reporting from San Salvador.