ATLANTA — After hearing numerous stories of immigrants being deprived of meals and relegated to harsh living conditions inside some detention centers across the country, Grammy-winning singer Miguel said he felt angered.

That’s why he decided to headline a free (hash)SchoolsNotPrisons concert in California to bring more awareness to the issue last month.

More than 1,000 attendees were at the show, held across the street from the Adelanto Detention Center, the largest in the state.

“You think a detention center is a place where people are being fed and taken care of, but these people are only getting one meal a day, which is often like a sandwich,” Miguel, who is half black and Mexican and was raised in Los Angeles, said in a recent interview.

“They sleep on the floor. The children that are being held there are sleeping under one blanket. …The food they are serving isn’t edible because it’s been spoiled or there are maggots in the food. The treatment is crazy,” he said.

Detention centers are institutions that usually hold people, particularly immigrants, for short periods of time while they await trial or a sentence. But the R&B singer said he’s heard firsthand stories from people who have been held for nearly a decade.

Miguel believes those types of institutions should be shut down. He said though some of the inmates are criminals, the majority of them are looking to better their lives and seek opportunities in the U.S.

The singer said he empathized with them, especially since his grandmother came to the United States from Mexico to find work in the 1960s. She eventually moved her family to America.