Homeland Security Secretary Kirstjen Nielsen told lawmakers Wednesday she expects the department to apprehend 900,000 illegal immigrants at the border this year, both between ports of entry and at border crossings.

"Our nation is facing a dire humanitarian and security crisis at our southern border," Nielsen told the House Homeland Security Committee. "The agency is now on track to apprehend more migrants crossing illegally in the first six months of this fiscal year than the entirety of FY17."

"The total number we're on track for — 900,000 apprehensions this year," she said.

Slightly more than 310,000 people were arrested for illegally crossing into the U.S. in all of 2017. Another 216,000 were turned away at ports for lacking legal documents to enter.

From October through January, approximately 60,000 people each month were either arrested after illegally crossing or after trying to cross at a border crossing point without legal permission.

U.S. Customs and Border Protection announced Tuesday more than 76,000 people were encountered in February, making it the largest monthly number in 12 years.

In 2018, a total 683,000 undocumented immigrants tried to illegally enter the U.S. at ports or between border crossings.

CBP said Tuesday they expect the numbers to continue spiking this spring. During President Trump's first few months in office, monthly apprehensions dipped to 17,000 people.

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