Last week, Presner Nelson went to a shopping mall with one goal in mind: to find a suit his brother, who died in immigration federal custody in March, would wear in his casket.

Nelson's brother, Emmanuel Damas, died after allegedly complaining for roughly two weeks of a toothache that Nelson believes could have been treated.

"This was the first time I had to do this in my life -- it was not easy," Nelson told ABC News.

The death of Damas, a Haitian immigrant who Nelson says arrived in the U.S. legally and had a pending Temporary Protected Status application, comes amid growing concerns from lawmakers and immigrant advocates about the conditions in migrant detention facilities, and a sharp increase in immigrant deaths in detention under the second Trump administration as it pursues its immigration crackdown.

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