US immigration officials say they have temporarily released about 300 people who were arrested in a massive raid in Mississippi on Wednesday.
Nearly 700 workers from seven agricultural processing plants were arrested for allegedly not having proper documentation to be in the US.
The raids sparked condemnation from Democrats as stories emerged of children separated from their parents.
Officials say they took steps to ensure any children were properly cared for.
Immigration and Customs Enforcement (ICE) said "approximately 680 removable aliens" had been detained during the operation, which saw agents arriving in buses to question and arrest workers at the plants.
President Donald Trump had announced an immigration crackdown in June, saying "millions of illegal aliens who [had] found their way into the US" would be removed.
What did ICE say?
ICE spokesman Bryan Cox told the BBC that, of the 680 people arrested in Wednesday's raids, more than 300 had been released with notices to appear before immigration judges.
"They were placed into proceedings before the federal immigration courts and will have their day in court at a later date," he said in an emailed statement.
Those who were not released will be moved to an ICE detention facility and held there, Mr Cox said.
About 30 of the people detained were released on humanitarian grounds, the US Attorney's Office for the Southern District of Mississippi said.
Mr Cox said those arrested were asked if they had any dependents needing care or if they had any children at school who needed to be picked up.
They were given access to phones at the processing site to make arrangements to care for their children. He said those with child care issues were "expeditiously processed and returned".
In response to critics who called the raids cruel and harmful to the workers' children, Mr Cox said the agency had directed two Homeland Security Investigations employees to notify schools of the operation and provide contact details for any children whose parents did not pick them up.
"This agency took extensive steps in planning for this operation to take special care of situations involving adults who may have childcare situations or children at school at the time of their arrest."
Those detained had been taken to a Mississippi National Guard hangar for questioning.
ICE did not share details about the nationalities of those detained, but the Mexican government has reportedly sent consular staff to the area to help any of their nationals who may be involved.