CIUDAD ACUÑA, Mexico — The Biden administration Sunday began deporting people from the makeshift camp where nearly 14,000 migrants have gathered beneath a South Texas bridge amid food shortages and deteriorating sanitary conditions.

Three flights carrying 327 Haitian nationals landed in Haiti on Sunday, according to two U.S. officials who spoke on the condition of anonymity because they were not authorized to release the information. In a midday news conference, Border Patrol Chief Raul Ortiz said the federal government had moved 3,300 individuals from the camp Sunday to migrant processing facilities. The government enlisted the help of the local school system to transport people on school buses to facilities in Texas in San Antonio, Laredo and Eagle Pass, he said.

“We are working around-the-clock to expeditiously move migrants out of the heat, elements and from underneath this bridge to our processing facilities in order to quickly process and remove individuals from the United States consistent with our laws and our policies,” said Ortiz, adding it will be done in a “humane and timely manner.”

The Biden administration is conducting the deportations under Title 42, the Trump-era public health order that President Biden has kept in place to push migrants south of the border during the covid-19 pandemic.

The goal is to reduce the number of people waiting to be processed by U.S. Customs and Border Protection personnel and improve conditions on the ground. It’s also designed to break the momentum and determination of migrants who have been encouraged by their U.S. relatives to make the journey before the opportunity passes or their individual circumstances worsen.

Migrants attempting or considering the journey to the border, “should know we are still enforcing CDC Title 42 order and they will not be allowed to enter the United States. They will be removed and they will be sent back to their country of origin,” Ortiz said.

But news of the deportation flights has not stopped or worn down the resolve of some migrants.

Near the encampment Saturday, Melisa Joseph ticked off the names of all the countries she and her family journeyed through on their way to the Rio Grande’s steep, thorny embankment near Texas.

“Bolivia, Peru, Colombia, Panama and Costa Rica. I think it was nine countries,” the 24-year-old told another woman in her Creole-tinged Spanish, the fruit of three years living in Chile. “Maybe it was 10.”

Deteriorating social and economic conditions — worsened by the pandemic — in the South American country became too hostile to bear for Joseph, forcing her, her husband and two young children to join a persistent exodus of her compatriots to the northern half of the Americas. Racism, perpetual deportation threats and tightening work restrictions on foreigners in Chile made the choice inevitable, but Joseph never imagined what she found at the river’s edge in Mexico.

From the neighborhood alleyways of Ciudad Acuña overlooking the Rio Grande emerged a surreal sight: A highway of humanity, many of them fellow Haitians, crisscrossing the international boundary unfettered as if it were a New York City intersection during rush hour and not the heavily surveilled dividing line between two global powers.

No one was hiding. There was no hesitancy. Everyone — carrying cases of water, bags of food, mattresses and blankets — looked like they had somewhere important to be.

“I never expected any of this,” the bewildered Joseph said as she prepared to make her own crossing, grabbing a bag of recently bought groceries. “We go with fear, but we go determined to make the sacrifices for our families. We got this far.”

While it’s not clear how or why thousands of specifically French-, Creole- and Spanish-speaking Haitians converged simultaneously on this isolated outpost of the U.S.-Mexico border, what is clear is that many of their migration stories began long ago. Theirs is an unending tale of displacement, discrimination and deportation that many had hoped would end in Del Rio, Tex., and lead to a permanent home.

Their motivations for migrating are complicated yet similar. The routes they traverse are dangerous and unpredictable. But their crowding by the thousands — with many more reportedly on their way — onto a dusty piece of dirt bereft of proper sanitary conditions, medical resources or shelter, has provoked an overwhelmed government to threaten these immigrants with removal to homelands they hoped never to return.

Jorge Rios, 28, and his cousins have been guarding their family property in Mexico since early this week when the first cascades of migrants washed over this small town. Local police asked Rios’s family to open a passage to the river embankment behind their home. Migrants, press and police are the only ones allowed through. Rios stopped a pair of Mexican teens warning them not to trespass on his property: “Mexicanos, no,” he said. “Migrantes, si.”

“I’ve never seen anything like this before,” said Rios, whose family pulled out power strips from inside the home allowing migrants to charge their phones. “More than 10,000 people have walked through our backyard. And more are coming. These migrants have families en route, and they have families who already made it through weeks before them.”

Mexican municipal police are monitoring the throngs. One bored officer stood at the mouth of a torn chain-link fence occasionally rebuking migrants to wear masks. At one point, the officer gave up saying anything.

The narrow dirt paths leading down the Mexican bluff are well-worn but susceptible to tumble. People step lightly as they carry giant bottles of water on their heads and babies in their arms. Some migrants tie their shoes together by the laces and wrap them around their necks. They roll up their pants up to their underwear before stepping down into the swift, knee-high water.

Walking across the concrete spillway is like trudging through goop, stepping slowly and warily so as not to fall victim to the deceptively swift current. It is not easy to avoid the clumps of algae and mysterious brown-colored muck the river carries. A group of fishermen and snorkelers cast spears and line into the river, unbothered and seemingly oblivious to the spectacle unfolding around them.

Before Saturday afternoon, law enforcement was largely absent from this river crossing. But after more state and federal officers surged to the border, a caravan of police vehicles and helicopters descended on the U.S. side of the spillway where people were bathing and washing out plastic bottles for re-use. As a lightning storm darkened the sky, Texas state troopers yelled at migrants to clear the spillway, cordoning off the area and closing river access to the itinerant camp residents.

Gusting winds ripped apart the new “No Trespassing” sign they had attached to the rope. Troopers secured and now guard the once-unrestricted byway.

The window for cross-river commerce appeared to have been suspended and possibly, over for good. Microeconomies had developed over days within the camp. Men bought boxes of food in Ciudad Acuña’s plazas and food trucks to resell to desperate and hungry families. Women bought extra blankets and diapers to make an extra buck. Wherever there is people, there is money and the opportunity to make more, migrants said.

Cutting off access to Mexico could be problematic for the masses underneath the bridge. In the streets of the border city, Brenda Martinez of the local charity Bridge Builders for the Cross, handed out free masks, T-shirts and sanitary napkins to the migrants from the back of a pickup. It was important to her that the migrants obtain basic goods that may not be available at the camp. Their shirts said in Spanish, “Helping people is my passion.”

Limiting migrants’ ability to cross into Mexico or use the river to bathe would complicate matters at the camp where sanitation is largely absent. Migrants said the portable toilets are foul. The dust, dirt and sweat are ubiquitous and the river offers the only viable option to clean.

Before this latest mass of migrants, Haitians, Venezuelans and Cubans regularly opted for the Ciudad Acuña-Del Rio crossing point to surrender to Border Patrol. They had been told by other migrants, compatriots and family members who had gone before them that once in custody, there was a high likelihood they would be released. CBP data for the sector confirms their assumptions.

Upon reaching soil and contacting agents, migrants would insist on changing at the shore into their better clothes and shoes and cleaning up a bit. They knew they would soon be in an airport or on a bus to meet their waiting relatives within hours.

That is what Gerlin Dominguez, who traveled from Venezuela, expected before encountering the camp. The conditions surprised her. There are so many people and it is so loud that one can hear the drone of what sounds like a stadium full of voices from more than a mile away.

Buying things in Mexico, including soap and wipes, is a boon to the local businesses but its also imperative for the migrants because there is nothing at the camp. The food handed out by federal authorities runs out quickly and the chips and bread they hand out are not sustenance, she and other migrants said.

“There’s no space. It’s dusty, dirty and not at all what I hoped to find,” said Dominguez while walking alongside her 5-year-old son, Ramses. The boy is sleeping on a piece of old cardboard beneath a crude hut made of bamboo-like cane and draped with blankets over top. “It’s the children who are suffering the most.”

While city and county officials fear agitation and restlessness could lead to violence or unrest, Dominguez said most migrants endure calmly, holding on dearly to their ticket numbers and are careful not to do anything to compromise their spot in line.

“We gave up everything we had to be here,” the 30-year-old said. “We are not going to give up that easily.”

Nick Miroff contributed to this report.