U.S. Marshal deputies direct several suspected illegal immigrants from the federal courthouse Tuesday in Hattiesburg, Miss., to a waiting van for transportation to an overnight holding facility. The immigrants were detained Monday in a raid on a manufacturing plant in southern Mississippi. More than 600 suspected illegal immigrants were picked up during the raid.

Laurel, Miss. ? The largest single-workplace immigration raid in U.S. history has caused panic among Hispanic families in this small southern Mississippi town, where federal agents rounded up nearly 600 plant workers suspected of being in the country illegally.

One worker caught in Monday’s sweep at the Howard Industries transformer plant said fellow workers applauded as immigrants were taken into custody. Federal officials said a tip from a union member prompted them to start investigating several years ago.

Fabiola Pena, 21, cradled her 2-year-old daughter as she described a chaotic scene at the plant as the raid began, followed by clapping.

“I was crying the whole time. I didn’t know what to do,” Pena said. “We didn’t know what was happening because everyone started running. Some people thought it was a bomb, but then we figured out it was immigration.”

About 100 of the 595 detained workers were released for humanitarian reasons, many of them mothers who were fitted with electronic monitoring bracelets and allowed to go home to their children, officials said.

About 475 other workers were transferred to a U.S. Immigration and Customs Enforcement facility in Jena, La. Nine who were under 18 were transferred to the custody of the Office of Refugee Resettlement.

John Foxworth, an attorney representing some of the immigrants, said eight appeared in federal court in Hattiesburg on Tuesday because they face criminal charges for allegedly using false Social Security and residency identification.

He said the raid was traumatic for families.

“There was no communication, an immediate loss of any kind of news and a lack of understanding of what’s happening to their loved ones,” he said. “A complete and utter feeling of helplessness.”

The superintendent of the county school district said about half of approximately 160 Hispanic students were absent Tuesday.

Roberto Velez, pastor at Iglesia Cristiana Peniel, where an estimated 30 to 40 percent of the 200 parishioners were caught up in the raid, said parents were afraid immigration officials would take them.

“They didn’t send their kids to school today,” he said. “How scared is that?”

Those detained were from Brazil, El Salvador, Germany, Guatemala, Honduras, Mexico, Panama, and Peru, said Barbara Gonzalez, an ICE spokeswoman.