Washington — The number of migrants apprehended by U.S. immigration agents after crossing the southern border illegally has soared to near-record levels in September, posing a major test to the Biden administration's migration strategy, unpublished federal figures obtained by CBS News show.

Border Patrol agents apprehended roughly 140,000 migrants who crossed the U.S.-Mexico border without authorization during the first 20 days of September, an average of about 6,900 each day, according to the internal agency data. That represents a 60% increase from the daily average of 4,300 in July.

The agency is on track to record more than 210,000 migrant apprehensions this month, which would be the highest level since December and May 2022, when Border Patrol reported over 220,000 apprehensions, the current all-time monthly highs. During those record-setting months, Border Patrol apprehended more than 7,000 migrants each day, a level September's average is close to matching.

On Wednesday alone, Border Patrol processed nearly 9,000 migrants, the data show, a daily apprehension level not seen since 10,000 migrants crossed into the U.S. illegally per day during several days in May, before the Biden administration discontinued the Title 42 pandemic-era limits on migration. 

Moreover, U.S. border officers have been processing roughly 1,500 migrants at official ports of entry on a daily basis, mostly under a Biden administration system that allows prospective asylum-seekers in Mexico to secure an appointment to enter the country through a government phone app known as CBP One.

The spike in illegal border entries is a significant setback for a web of policies the Biden administration initiated in the hopes of slowing down U.S.-bound migration. Over the past two and a half years, Border Patrol has recorded unprecedented levels of migrant apprehensions, including 2.2 million in fiscal year 2022, a tally that is on track to being matched in fiscal year 2023, which ends at the end of this month.

Following the end of the Title 42 public health expulsions in May, the Biden administration implemented a set of policies to discourage unauthorized entries. The strategy has consisted of redirecting tens of thousands of migrants to enter the U.S. each month through legal migration programs, including the app-powered process, while imposing higher asylum rules for those who cross into the country unlawfully.  

Administration officials touted the strategy when illegal border crossings dropped below 100,000 in June, a two-year low. But the trend was quickly reversed in July, when unauthorized crossings increased to 133,000, a 33% month-month jump. In August, Border Patrol apprehended roughly 180,000 migrants, according to preliminary agency data.

The increase in migration is happening across the Western Hemisphere. In August alone, more than 80,000 people crossed Panama's Darién Gap, a monthly record high for a roadless and mountainous jungle that has become a major transit destination for hundreds of thousands of migrants hoping to reach the U.S. each year, according to Panamanian officials.

Influx strains federal and local resources

The spike in migration has strained federal and local resources. In some areas of Arizona and southern California, Border Patrol has recently found itself forced to release migrants into communities to prevent overcrowding in facilities. Last month, Border Patrol agents in Texas temporarily separated children as young as 8 from their parents, citing concerns about overcrowding in a facility, a federal court-appointed inspector found.

In the Texas border cities of El Paso and Eagle Pass, federal border officials have suspended processing of commercial trucks and vehicles at some international bridges, so agency employees can be diverted to help process migrants. The mayor of Eagle Pass this week issued a disaster declaration, citing the daily arrival of thousands of migrants to the small city.

On Wednesday, the Biden administration announced the Pentagon had approved a plan to send an additional 800 active-duty troops to the southern border to provide logistical support to Border Patrol. Roughly 2,500 troops are already stationed there, performing operational tasks, not arresting migrants.

The administration also said it would increase deportations of migrants, including by expanding a fast-track removal program for families that requires the heads of households to comply with a nightly home curfew and wear an ankle monitor while officials determine whether they could qualify for asylum.

Since the end of Title 42 in May, the U.S. has deported or returned 253,000 migrants to over 150 countries, including 36,000 parents and children processed as families, the Department of Homeland Security said Wednesday. During the same time period in 2019, the department said it carried out 180,000 deportations and returns.

The impact on cities

The influx in illegal crossings has also impacted large cities in the northern U.S., mainly New York City, which for months has struggled to house tens of thousands of destitute migrants in need of shelter. The city has set up migrant shelters in over 200 hotels, tents and other facilities but has regularly demanded increased federal funds and support.

On Wednesday, the Biden administration granted a long-standing request from New York and other cities receiving asylum-seekers, offering nearly half a million Venezuleans migrants an opportunity to work and live in the U.S. legally under the Temporary Protected Status program. Only Venezuelans who arrived in the U.S. before the end of July will qualify for work permits and deportation protections.

While there's a July 31 cut-off date for the TPS program for Venezuelans, some government officials have long feared that expanding the policy risks encouraging more migrants to enter the U.S. illegally, even if they are not eligible for the relief on paper, because of misinformation by smugglers.

In a recent interview, former Border Patrol chief Rodney Scott, who left the agency after a few months in the Biden administration, said the spike in illegal crossings this summer stems from the U.S. releasing large numbers of migrants into the country with court cases that typically take years to complete. Migrants who are released, Scott said, can tell family and friends in their home countries that there are higher chances of being released into the U.S. and staying in the country for years if they cross the border illegally.

Biden administration officials have said the high levels of migration mainly stem from dire conditions in countries like Cuba, Nicaragua and Venezuela, which has seen millions of its citizens flee economic calamity and political tumult in recent years, mostly to resettle in other South American nations like Colombia. 

During a briefing Wednesday, a senior DHS official also faulted smugglers for the recent increase in migration, saying they "spread rumors" that "drive people to cross" into the U.S. illegally.

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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