Ms. Peralta, 63, said that families were working together to cope. It was rare, she said, that both members of a couple were working at the plant, and many extended families lived together. This meant that most children had someone to look after them, unlike those east of town, in Forest, Miss., where children of people caught in the raid were reportedly left in the care of neighbors and strangers, and a local gym was opened to offer them a place to sleep.

In tearful videos and images that ricocheted across social media, children whose migrant parents had been rounded up pleaded with the United States government to release their mothers and fathers.

“Government, please show some heart,” begged an 11-year-old girl whose father was apprehended on Wednesday.

Dozens of children, some as young as toddlers, were bewildered when they were picked up from school and taken to makeshift shelters, including the gym in Forest, where the owner fed them dinner with food donated by residents.

Videos showed children crying in corners or in the arms of friends, neighbors and strangers. On Thursday afternoon, state officials, immigration advocates, and lawyers still did not have a clear picture of what had happened to those children, or who had taken custody of them.

The Mississippi Department of Child Protection Services said that no child was in its custody.

On Thursday afternoon, the United States attorney’s office for the Southern District of Mississippi said that all detainees had been asked if they had a child at school or day care. Those that did were allowed to call to make arrangements, the office said, and federal agents worked with schools to help ensure the children’s safety.