MARFA, Texas (CBSDFW.COM) – A branch of the U.S. Customs and Border Protection rescued a group of over a dozen illegal aliens who were lost near the Big Bend area and suffering from extreme hypothermia Friday morning.

The Air and Marine Operations found 15 men and women and began rendering medical assistance. One of the 15 was pronounced dead upon the agents’ arrival.

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Officials say the 14 surviving people were all in various states of distress and hypothermia as they were found lost in the desert in the Big Bend area of West Texas.

According to officials, the people are illegal aliens from Guatemala and were walking through the desert for about a week.

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(Credit: U.S. Customs and Border Protection)

The Big Bend area was under a winter storm warning last Wednesday.

“While the loss of even one life is tragic, the heroic efforts of our expertly trained agents responding to this chaotic, mass-casualty event clearly saved 14 lives from certain death,” said Supervisory Air Interdiction Agent and Air and Marine Emergency Medical Services Program Manager Jeff Birks. “Their immediate and enduring response, under the harshest of conditions, reflects great credit upon themselves and our agency.”

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The 14 immigrants continue to be held.