In this file photo dated December 22, 2021, migrants heading in a caravan towards the US wait for buses at the House of the Pilgrim San Juan Diego in Mexico City. ALFREDO ESTRELLA AFP WASHINGTON - US border authorities arrested 210,000 migrants trying to cross the border with Mexico in March, the highest monthly total in two decades and underscoring challenges for US President Joe Biden in the coming months.
The March total is a 24 percent increase from the same month a year earlier, when 169,000 migrants were picked up at the border, the start of a rise in migration that left thousands of children trapped in crowded border patrol stations for days while they wait for placement in government-run shelters.
Biden, a Democrat who took office in January 2021, pledged to reverse many of the hardline immigration policies of his Republican predecessor, former President Donald Trump, but has struggled both operationally and politically with high numbers of attempted crossings.
The Republicans who hope to gain control of the US Congress in Nov 8 midterm elections say that Biden's rollback of Trump-era policies has encouraged more illegal immigration.
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Biden officials cautioned that migration could rise further after US health officials said they will end a Pandemic-era border order by May 23. The order, known as Title 42, allows asylum seekers and other migrants to be quickly expelled to Mexico to prevent the spread of COVID - 19.
More than half of the migrants encountered at the US-Mexico border in recent months have been from the traditional sending countries of El Salvador, Guatemala, Honduras, and Mexico, but migrants have been arriving from more far-flung places, including Ukraine and Russia.
US officials are preparing for as many as 18,000 migrant encounters per day in the coming weeks, but are also ready for smaller increases.
In March, the 210,000 people arrested in March, the highest monthly total since February 2000, according to US Customs and Border Protection statistics dating back to 2000, was made public in a court filing on Friday night.
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The court filing said that another 11,000 migrants tried to enter a legal crossing along the southwest border in March without a valid visa or permission.
The court filing said that more than half of the migrants encountered in March were expelled under the Title 42 order.