U.S. immigration authorities say an 8-year-old boy from Guatemala has died in government custody, the second immigrant child to die in detention this month.

U.S. Customs and Border Protection say the boy died shortly after midnight Tuesday.

CBP says the boy showed "signs of potential illness" Monday and was taken with his father to a hospital in Alamogordo, New Mexico. There, CBP says, he was diagnosed with a cold and a fever. He was given medications and released Monday afternoon.

The agency says the boy was returned to the hospital Monday evening with nausea and vomiting. He died just hours later.

A CBP spokesman declined to elaborate Tuesday, but said details will be released shortly.

A 7-year-old Guatemalan girl died earlier this month after being apprehended by border agents.