(CNN) A 2-year-old boy from Guatemala died at a hospital in El Paso, Texas, this week over a month after being apprehended by US immigration authorities as he crossed the border with his mother, the Guatemalan Consulate said Thursday.

The boy, who was not identified and was not in US custody at the time of his death on Tuesday, had suffered from complications of pneumonia, Tekandi Paniagua, the Guatemalan consul general in Del Rio, Texas, told CNN.

The boy is the fourth child known to have died after journeying to the US in recent months from Guatemala, where poor economic conditions have driven record numbers of migrants to the US. The death was first reported by The Washington Post.

In April alone, the Border Patrol arrested 98,977 migrants for illegal entry, many of whom were families -- an increase from the month before. Migrants from Central America often make the journey through Mexico under punishing conditions and with limited food and water.

Immigration officials have noted a recent increase in illnesses in migrants arriving in the US, and advocates have argued that conditions at US holding facilities can be unsafe.

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