President Joe Biden believed scenes of border patrol agents on horseback intimidating Haitian migrants were “horrific and horrible” and supports a Department of Homeland Security investigation into the matter, his top spokeswoman said today.

“I don’t know anyone who could watch that video and not have that emotion,” White House Press Secretary Jen Psaki said in an interview with CBS News.

The U.S. Customs and Border Protection’s Office of Professional Responsibility launched a probe into the incident in Del Rio, Texas, on Monday to determine possible disciplinary action. Video from the site showed asylum-seeking migrants shielding their heads as agents on horseback appeared to brandish their reins like whips.

One agent rides up to a group, some carrying children, and insults them and Haiti. A woman and child rush to get out of his way. Other migrants fall into the river as the horsemen advance.

“I think it’s important for people to know this is not who we are,” Psaki said. “That’s not who the Biden-Harris administration is, and we’re going to absolutely pursue that investigation and get to the bottom of what happened here.”

Vice President Kamala Harris echoed the concern during a child-care event later today, saying she was “deeply troubled” and planned to speak to Homeland Security Secretary Alejandro Mayorkas about the situation later in the day.

“What I saw depicted about those individuals on horseback, treating human beings the way they were, is horrible,” Harris said. “And I fully support what is happening right now, which is a thorough investigation into exactly what is going on there.”

The Department of Homeland Security also said Monday night it would dispatch additional personnel to the border to help oversee operations as a growing group of Haitians seek entry into the U.S.

Senate Majority Leader Chuck Schumer today said the “horrible images” capturing the treatment of Haitian immigrants at the southern U.S. Border show they “have been met at our doorstep with unimaginable indignity.”

He also criticized the Biden administration’s plans to send many of the Haitians to their home country, which is in turmoil after the assassination of its president and an earthquake. He said he had been told there are four flights scheduled to deport the asylum seekers “back to a country that cannot receive them.”

“The policies that are being enacted now and the horrible treatment of these innocent people who have come to the border must stop immediately,” Schumer said on the Senate floor. He said he will work with the administration to ensure more resources are provided to establish more humane processing of the migrants.

The DHS Office of Inspector General has also been alerted to the incident, the administration said in a statement.

“I was horrified by what I saw,” Mayorkas said in an interview with CNN today. “I’m going to let the investigation run its course. But the pictures that I observed troubled me profoundly. That defies all of the values that we seek to instill in our people.”

Some of the migrants had been in Latin American countries for some time before trying to reach the U.S. The latest influx has coincided with the assassination of Haitian President Jovenel Moise in July and a major earthquake in August that further traumatized the impoverished Caribbean nation.

Thousands of the migrants have set up an improvised camp under a bridge in Del Rio, Texas. The camp has drawn sharp criticism of Biden and his immigration policies both from civil liberties and human rights groups and conservatives, including former President Donald Trump.

A White House official said Monday night the administration was trying to respond to the crisis by providing support to the migrants at the border but also by flying them back to Haiti under Title 42, which allows for their rapid expulsion due to the threat of bringing communicable disease into the country. Psaki said Monday that two flights a day were traveling from the U.S. to Haiti.

The State Department said Monday night that Secretary of State Antony Blinken had spoken with Haitian Prime Minister Ariel Henry “about cooperation to repatriate Haitian migrants on the southern border of the United States.”