(CNN) US Border Patrol arrests on the southern border increased for the first time since last May, the height of the migration crisis on the US-Mexico border, according to data obtained by CNN.

The agency apprehended 30,068 migrants illegally crossing into the US from Mexico in February, up from around 29,200 in January, the unofficial data and last month's reported numbers show.

However, the numbers are far below last year. Last February, 66,883 people were arrested on the southwest border.

The uptick comes days after a federal appeals court dealt a major blow to the administration's immigration agenda, blocking a policy to send migrants to wait in Mexico for their US court dates. US officials have touted this program for helping reduce the number of people illegally crossing the border.

"Rulings like this, it threatens our progress," said acting Customs and Border Protection Commissioner Mark Morgan at a press conference Thursday.

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