Border Patrol has processed more migrants who entered the U.S. illegally in December than in any other month in the agency's history, internal federal statistics obtained by CBS News show, highlighting the magnitude of the extraordinary migration crisis the Biden administration is grappling with.

U.S. Border Patrol agents took into custody more than 225,000 migrants who crossed the southern border — in between official crossings — during the first 27 days of December, according to the preliminary Department of Homeland Security statistics. The figure does not include legal entries at ports of entry, where the Biden administration has been processing roughly 50,000 migrants each month, mostly under a process powered by a smartphone app.

The previous monthly record high in migrant apprehensions was recorded in May 2022, when Border Patrol processed 224,000 migrants in between ports of entry. There are still four days left in December.

The current spike in migration peaked before Christmas, during the week starting on Dec. 14 and ending on Dec. 20, when Border Patrol averaged 9,773 daily apprehensions, according to the data. On several days that week, the agency processed more than 10,000 migrants in 24 hours.

Unlawful crossings along the U.S.-Mexico border have decreased this week, but remain at historically high levels. On Wednesday, Border Patrol processed 7,759 migrants, the statistics show.

"It's an unsustainable number of arrivals," said Theresa Cardinal Brown, a former U.S. immigration official under Presidents George W. Bush and Barack Obama. "We can't keep funding the system for more and more people. It's challenging at every level."  

Nearly 60% of all migrants processed by Border Patrol this month crossed into the U.S. illegally in the remote Tucson, Arizona and Del Rio, Texas sectors, where officials have recorded between 2,000 and 3,000 unlawful crossings each day, according to the internal DHS data. In both regions, migrants have found themselves sleeping outdoors near international bridges or border barriers because Border Patrol lacks the manpower and resources to process everyone in a timely fashion. 

In a statement, Customs and Border Protection, Border Patrol's parent agency, said it had dispatched additional agents and resources to these hard-hit sectors.

"Encounter numbers continue to fluctuate, as smugglers and bad actors continue to spread falsehoods and show complete disregard for the safety and wellbeing of vulnerable migrants," the agency added. "We remain vigilant and stand ready to ensure the safety of our personnel, migrants, and local communities, and the security of our southwest border."

A high-stakes moment for the Biden administration

The record levels of migrant crossings this month vividly illustrate the daunting logistical, humanitarian and political challenges President Biden faces at the U.S. southern border. 

Politically, Mr. Biden's woes on immigration are clear as he faces reelection in 2024. Public polling, including by CBS News, has consistently indicated that most Americans view his administration's handling of border and immigration issues unfavorably. 

While Republicans have criticized Mr. Biden's immigration agenda since his first months in office in 2021, the president is facing a growing chorus of concerns from fellow Democrats across the country.

Small U.S. border communities like Eagle Pass, Texas; Jacumba Hot Springs, California; and Lukeville, Arizona, have suddenly become major transit points where thousands of migrants enter the country unlawfully every day, despite the coils of razor wire or federal border walls in their paths. The influx in illegal entries has strained local and federal resources in these remote regions, prompting local and state officials to request more federal support.

Meanwhile, large U.S. cities like Chicago, Denver and New York City have continued to struggle to accommodate tens of thousands of migrants, many of whom are destitute and lack ties to the U.S. On Wednesday, the Democratic mayors of the three cities warned that without increased federal assistance, they would soon be unable to receive more migrants.  

In a statement Thursday, White House spokesperson Angelo Fernández Hernández said the Biden administration had helped 10,000 migrants in city shelters apply for work permits, expedited the review of these applications and approved millions of dollars in funds for communities receiving new arrivals.

In Congress, Republican lawmakers have conditioned additional military aid to Ukraine to drastic restrictions on asylum and new legal authorities to swiftly deport migrants. Committed to dispatching more aid to Ukraine and addressing the dire challenges at the southern border, the White House is entertaining some of the hardline border policies championed by Republicans. The negotiations between lawmakers and the White House are expected to continue into the new year. 

The scale of the crisis along the southern border intensified so much this month that the White House dispatched top U.S. officials, including Secretary of State Antony Blinken and Homeland Security Secretary Alejandro Mayorkas, to Mexico City on Wednesday to meet with Mexican President Andres Manuel Lopez Obrador to get his help in curbing U.S-bound migration.

The White House National Security Council said Mexico had taken "significant new enforcement actions" to reduce migrant arrivals along the U.S. border, though it did not offer further details on those operations. It did say officials from both countries would meet again in Washington in January "to assess progress and decide what more can be done."

In:
• Immigration
• U.S.-Mexico Border
• Migrants

Camilo Montoya-Galvez

Camilo Montoya-Galvez is the immigration reporter at CBS News. Based in Washington, he covers immigration policy and politics.

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