Updated at 2:38 p.m. ET
An 8-year-old boy from Guatemala has died in government custody, U.S. Customs and Border Protection says.
The boy died shortly after midnight on Tuesday, at a hospital in Alamogordo, N.M. He is the second child this month to die in CBP custody after being apprehended by the agency.
The child was initially sent to Gerald Champion Regional Medical Center with his father during the day on Monday, according to a statement from CBP.
Hospital staff diagnosed the boy with a common cold and a fever, and released him in the mid-afternoon with prescriptions for antibiotics and ibuprofen.
He was transferred back to the hospital later that evening, after he began vomiting, and he died hours later.
CBP says it does not know the cause of the child's death.
A 7-year-old Guatemalan girl died of dehydration and septic shock while in government custody earlier this month. The girl, Jakelin Caal Maquin, had been apprehended in New Mexico after crossing the southern border into the U.S. illegally with her father.
Her death on Dec. 8 prompted calls for investigation from the Congressional Hispanic Caucus, which says "disturbing systematic failures" and a lack of medically trained agents prevented the government from adequately caring for its child.
Last week, a delegation from the caucus, including the chair Rep. Joaquin Castro of Texas, visited the facility where the girl had been held.
The Democratic congressman told reporters that officials failed to intervene in several instances when they could have saved Maquin's life.
Maquin and her father were taken to the Antelope Wells port of entry after turning themselves in to CBP officers in early December. The girl began vomiting during a bus transfer to Lordsburg Border Patrol Station.
By the time she arrived at the station, she had stopped breathing and had to be resuscitated. She was flown by helicopter to a hospital in El Paso, Texas, where she died.
The congressional delegation criticized the medical facilities at the Lordsburg station and questioned CBP's decision to transfer the girl to a second facility. Members also criticized the administration for demanding funding for a border wall, rather than ensuring that detention centers had sufficient resources.
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