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Hundreds of migrants from central African countries, including the Republic of Congo, Angola and Cameroon have been apprehended by U.S. Border Patrol in the past month. Federal officials in Texas reported more than 500 people from African countries were arrested in less than a week.
"Our Border Patrol agents are facing more unique challenges every day as the number of family units from different regions of the world continue to increase," Del Rio Sector acting Chief Patrol Agent Randy Davis said in a statement.
The new arrivals have further strained U.S. authorities, as agents who mostly process large numbers of Central American migrants are now dealing with translating different languages while initiating the asylum process.
The latest arrest reports far exceed last year's levels. For example, agents arrested 45 Eritreans, 33 Somalians and no one from the Republic of Congo or Angola at the southern border over the course of fiscal year 2018, according to U.S. Customs and Border Protection data.
Looking back further, one Eritrean, one Cameroonian, one person from the Republic of Congo and one from Angola were arrested for crossing illegally in the last full budget year of the Obama administration, according to CBP.
The latest wave of apprehensions includes the largest single group of Africans ever seen by authorities at the southern border. Agents in Texas arrested a group of 116 people from Angola, Cameroon and the Republic of Congo after they crossed the Rio Grande River near Del Rio on May 31.
"Large groups present a unique challenge for the men and women of the Del Rio Sector," regional chief Raul Ortiz said in a statement at the time. "This large group from Africa further demonstrates the complexity and severity of the border security and humanitarian crisis at our Southwest border."
Two groups of more than 30 Africans, mostly from the Republic of Congo and Angola, crossed the Rio Grande days later in the Del Rio area.
CBP does not regularly provide the countries of origin for migrants legally arriving through border checkpoints. That number has stayed relatively consistent, despite surges of migrants in recent months.
However, independent researchers have documented that thousands of migrants have been forced to wait for weeks or months before being allowed to enter legally.