President Joe Biden on Friday described violent scenes where US border guards on horseback confronted destitute Haitian migrants crossing from Mexico "outrageous" and promised "consequences."
"It was horrible," he told reporters at the White House in his first comments on the drama. "It's outrageous. I promise you: those people will pay.... There will be consequences."
Biden took office in January vowing to reverse what he called his Republican predecessor Donald Trump's inhumane policies at the southern border.
Trump, who regularly warned that US borders were being overwhelmed and claimed falsely that immigrants were bringing large scale crime and disease, focused much of his presidency on promises to control the frontiers.
One of Trump's signature issues was funding to build sections of wall along the Mexican border and to repair existing sections. The policy was hugely popular with his core supporters, whom he encouraged to chant "build the wall" at mass rallies.
Biden finds himself in a bind eight months into his presidency, with huge numbers of would-be migrants being apprehended after crossing illegally from Mexico, including 200,000 people in August.
Democrats accuse Biden of reneging on his promises, pointing to his decision to retain tough deportation rules, something the White House says is required due to Covid-19 restrictions.
At the same time, Biden is hammered daily by Republicans and the Fox News network which portrays the southern border as out of control and the White House as surrendering American security.
That conflict came into dramatic focus this month when border guards on horseback were photographed trying to block Haitian immigrants crossing on foot from Mexico after arduous journeys.
- Disturbing images -
Wielding long leather reins and dressed in some cases in clothing reminiscent of Westerns, the images for many evoked distressing images of vigilante justice or even the US slavery era.
At the same time, border facilities were clearly overwhelmed with the sudden appearance of thousands of desperate Haitians, who had traveled through much of Latin America to reach the United States, then camped en masse under a Texas bridge.
Faced with a simultaneous security and humanitarian crisis, the Biden administration allowed some of the more vulnerable migrants to register and enter the United States.
However, many of the Haitians were ordered to be flown immediately back to Haiti, the country they'd fled in some cases years earlier.
The US special envoy to Haiti resigned in protest Thursday, citing the "inhumane, counterproductive decision."
Stung by criticisms on the left that he is perpetuating Trump's policies, Biden on Friday stressed that he was outraged by the scenes at the border.
"That was horrible to see... people treated like they did," he said. "It's an embarrassment. It's beyond an embarrassment. It's dangerous. It's wrong. It sends the wrong message around the world (and) sends the wrong message at home."