Haitian migrants wade across the Rio Grande from Del Rio, Texas, to return to Ciudad Acuna, Mexico, Sunday to avoid deportation to Haiti from the U.S. The U.S. is flying Haitians camped in a Texas border town back to their homeland and blocking others from crossing the border from Mexico in a massive show of force that signals the beginning of what could be one of America’s swiftest, large-scale expulsions of migrants or refugees in decades. (AP photo)

DEL RIO, Texas — The options remaining for thousands of Haitian migrants straddling the Mexico-Texas border are narrowing as the United States government was ramping up expulsion flights to Haiti on Tuesday and Mexico began busing some away from the border.

More than 6,000 Haitians and other migrants had been removed from an encampment at Del Rio, Texas, U.S. officials said Monday as they defended a strong response that included immediately expelling migrants to their impoverished Caribbean country and faced criticism for using horse patrols to stop them from entering the town.

That was enough for some Haitian migrants to return to Mexico, while others struggled to decide on which side of the border to take their chances.

Jean Claudio Charles, 34, his wife and their 1-year-old son were stretching at dawn on Tuesday after sleeping on cardboard in a park by the river with 300 others who chose to return to Mexico from the U.S. side, some for fear of being deported and others because of a lack of food.

Charles said he did not want to leave the area, which is gradually becoming a new camp on the Mexican side, for fear of arrests.

“They are grabbing people, they bother us, especially Haitians because they identify us by skin,” he said.

On Monday, U.S. Department of Homeland Security Secretary Alejandro Mayorkas conceded it was a “challenging and heartbreaking situation,” but he issued a stark warning: “If you come to the United States illegally, you will be returned. Your journey will not succeed, and you will be endangering your life and your family’s life.”