Felipe Gomez Alonzo died during detention in the state of New Mexico, US Customs and Border Protection (CBP) confirmed on Tuesday. He was an 8-year-old from Guatemala.

CBP Commissioner Kevin McAleenan said in a statement that the child's death was a "tragic loss." He told CBS television on Wednesday: "This is an extraordinarily rare occurrence,"

Margaret Huang, executive director of Amnesty International USA, was harshly critical of the administration of President Donald Trump. She said the  "policies of cruelty toward migrants
and asylum-seekers at the border must cease immediately before any more children are harmed."

The boy's death came at a time when the US is undergoing a partial government shutdown, which was triggered by Trump's demand for border wall funding. 

The CBP has ordered medical checks on every child in its custody as a result of Gomez Alonzo's death.

An agency spokesman could not say how many children were currently in its custody. 

Unknown cause of death

On Monday, the boy had shown "signs of potential illness" and was taken with his father to a hospital. There he was diagnosed with a cold and a fever. He was held under observation for 90 minutes, prescribed amoxicillin and Ibuprofen, and then released.

But on Monday evening, the 8-year-old was brought back to the hospital with nausea and vomiting. He died there just hours later, CBP said.

Read more: Donald Trump's 'asylum ban' highlights dysfunctional US Congress

Second death in a month

Gomez Alonzo is the second migrant child to die in the custody of US border patrol. Earlier this month, seven-year-old Jakelin Caal died of shock and dehydration during detention. She was also from Guatemala and was detained along with her father in a remote part of New Mexico.

Democratic members of the US Congress, along with immigration advocates, have sharply criticized CBP's handling of Jakelin's death and questioned whether border agents could have prevented it or called for an evacuation by air ambulance sooner.

CBP has promised "an independent and thorough review."

jcg/jm (Reuters, AFP, AP)

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