The United States said Saturday it would ramp up deportation flights for thousands of migrants who flooded into the Texas border city of Del Rio, as authorities scramble to alleviate a burgeoning crisis for President Joe Biden's administration.

The migrants who poured into the city, many of them Haitian, were being held in an area controlled by US Customs and Border Protection (CBP) beneath the Del Rio International Bridge, which carries traffic across the Rio Grande river into Mexico.

Video footage showed thousands of people under and around the bridge and more walking across the river, clutching their belongings.

Haitian migrants cross the Rio Grande near the Del Rio-Acuña Port of Entry in Ciudad Acuña, Mexico
Haitian migrants cross the Rio Grande near the Del Rio-Acuña Port of Entry in Ciudad Acuña, Mexico AFP / PAUL RATJE

Del Rio Mayor Bruno Lozano told reporters there were over 14,000 migrants "waiting to be detained." He added that both local and federal authorities were dispatching personnel, buses and aircraft as part of the operation.

The port of entry at Del Rio has been temporarily closed, and traffic is being rerouted to relieve the bottlenecks that had formed at the bridge.

Homeland Security said it would "secure additional transportation to accelerate the pace and increase the capacity of removal flights to Haiti and other destinations in the hemisphere within the next 72 hours."

Haitian migrants have been flooding into the United States in recent months
Haitian migrants have been flooding into the United States in recent months AFP / PAUL RATJE

The statement also said the Biden administration was taking action to "reduce crowding and improve conditions for migrants on US soil," and working with "source and transit countries in the region."

Texas Republicans seized on the crisis to lash out at Biden.

Senator Ted Cruz blasted the president on Twitter, stating that: "Nobody who actually sees what's happening can think the inhumane Biden policies make sense."

Cars line up on the Texas border at the Del Rio International Bridge -- which is closed temporarily due to the influx of migrants -- on September 17, 2021
Cars line up on the Texas border at the Del Rio International Bridge -- which is closed temporarily due to the influx of migrants -- on September 17, 2021 AFP / PAUL RATJE

Republican Congressman Tony Gonzales meanwhile tweeted that "we're seeing the situation rapidly deteriorate in real time."

"Border patrol agents are doing everything they can but it's clear they need more support and they need it NOW."

CBP has dispatched 400 additional personnel to "improve control of the area," the Department of Homeland Security said in a statement, unveiling its plans to contain the situation.

Border authorities have been overwhelmed by the number of migrants crossing from Mexico seeking admittance to the United States, as well as an influx of migrants from Afghanistan in the wake of the Taliban's takeover of that country.

Haitian migrants buy food and supplies in Ciudad Acuna, Mexico September 18, 2021, crossing back and forth across the border to purchase provisions
Haitian migrants buy food and supplies in Ciudad Acuna, Mexico September 18, 2021, crossing back and forth across the border to purchase provisions AFP / PAUL RATJE

Political pressure had mounted on Biden to address the issue of immigration, with both Republicans and his fellow Democrats calling for quick action.

The US government processed and mostly expelled more than 200,000 migrants at the border in both July and August, the highest numbers in more than a decade.

Some said Biden's decision in late July -- after Haitian president Jovenel Moise's assassination -- to allow Haitians without US visas at the time to remain in the country offered an incentive for others to come.

"10,503 illegal aliens are under this bridge tonight because Joe Biden made a political decision to cancel deportation flights to Haiti," Cruz tweeted on Thursday.

But in Saturday's statement, the Department of Homeland Security said "regular expulsion and removal flights" were ongoing to Haiti, Mexico, Ecuador, and countries in Central America's Northern Triangle -- Guatemala, El Salvador and Honduras.

The number of Haitians crossing the southwest border into the United States has been surging for months.

Many come from South America, where they may have migrated years ago, especially after the country's January 2010 earthquake.

CBP said the "majority of migrants" would be expelled under the government's Title 42 policy curtailing immigration due to the Covid-19 pandemic.

"Those who cannot be expelled under Title 42 and do not have a legal basis to remain will be placed in expedited removal proceedings," CBP said.

Biden promised a more humane approach to immigration as compared to his predecessor Donald Trump, but the veteran Democrat has fought to stem the tide of migrants crossing the border since he took office in January.

Most are sent back, but many families and almost all unaccompanied minors are permitted to stay.

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