Story highlights Apprehensions at the border are surging, Homeland Security chief says

The agents are being sent to South Texas amid a surge in migrants

(CNN) US Customs and Border Protection is sending 150 extra agents to the Rio Grande Valley in South Texas as authorities report a surge in the number of undocumented children and families trying to cross into the United States from Mexico, the agency said Saturday.

In October, 46,195 people were apprehended on the border, compared to 39,501 in September and 37,048 in August, Department of Homeland Security Director Jeh Johnson said in a statement earlier this week.

"As a result, there are currently about 41,000 individuals in our immigration detention facilities -- typically, the number in immigration detention fluctuates between 31,000 and 34,000," he said.

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The extra agents are being assigned work in the immigrant processing centers in McAllen and Weslaco, Customs and Border Protection said in a news release. The move should free up local agents who are more familiar with the region, the agency said.

The extra agents are coming from the areas of Tucson, Arizona; San Diego; and Del Rio, Texas. They are expected to arrive as early as Sunday and will probably remain in South Texas at least two months, said Chris Cabrera with the National Border Patrol Council.

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