Rep. Joaquin Castro (D-TX) on Monday delivered a heartbreaking report about what he’s seen so far in detention facilities where the Trump administration is keeping immigrant children who have been separated from their parents.

Reporting on child detention centers that he visited in Brownsville, Texas, Castro said that he has encountered shockingly young children who have been kept away from their parents for several weeks now.

“The youngest child (boy) I’ve seen here so far who was separated from his family is 8 months old and has been here over a month, according to administrators,” Castro wrote.

The youngest child (boy) I’ve seen here so far who was separated from his family is 8 months old and has been here over a month, according to administrators. #FamiliesBelongTogether

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— Joaquin Castro (@JoaquinCastrotx) June 18, 2018

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Castro also said that there were a total of four “very young children” being held in the facility’s so-called infant room.

We visited the Infant Room where four very young children, including Roger the 8 month old, were being looked after by staff. We picked up and carried the children. #FamiliesBelongTogether

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— Joaquin Castro (@JoaquinCastrotx) June 18, 2018

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The Trump administration has been taking heat from Democrats, Republicans, and childhood health experts for its policy of separating the children of undocumented immigrants from their parents.

Dr. Colleen Kraft, the president of the American Academy of Pediatrics, told CNN on Monday that the Trump administration’s policy amounts to “child abuse,” as she claimed treating children this way “disrupts their brain architecture and keeps them from developing language and social emotional bonds.”