US immigration officials have arrested almost 700 people after a series of raids in the state of Mississippi.
The co-ordinated operations targeted workers at seven agricultural processing plants who allegedly did not have proper documentation.
Videos and photos showed agents arriving in buses to question and arrest the people.
Some children were taken to a local gym after they came home to find their parents gone.
Immigration and Customs Enforcement (ICE) said “approximately 680 removable aliens” had been detained.
US President Donald Trump announced an immigration crackdown in June, saying “millions of illegal aliens who [had] found their way into the US” would be removed.
The raids took place just hours before Mr Trump arrived in the majority Latino city of El Paso to mark a mass shooting which left 22 people dead.
About 600 ICE agents arrived at the chicken processing plants, owned by five different companies, in the towns of Bay Springs, Canton, Carthage, Morton, Pelahatchie and Sebastopol.
The agency’s acting director, Matthew Albence, told the Associated Press news agency the raids could be “the largest-ever workplace operation in any single state”.
Friends and family looked on as officers surrounded plants and began to arrest the workers.
One video posted on Facebook showed people gathered outside a Koch Foods plant in Morton.
A child – daughter of one of the detained women – can be heard weeping uncontrollably as people are loaded onto a bus.
“Her mum is in there,” a woman tells a police officer. “Her mum is her only legal guardian.”
The crying girl asks the officer, “Please, can I just see my mother, please.” The child was eventually allowed to see her mother before she was taken away.
Those gathered outside reportedly chanted, “Let them go!” and waved goodbye as the buses drove off.
Mr Albence said the children would be sent to live with relatives or with other families, according to AFP news agency.
Some were taken to a local gym by neighbours after coming home from school to find their parents gone.
Those detained were taken to a Mississippi National Guard hangar for questioning.
According to a statement released by ICE, some may be temporarily released after “consideration of their criminality and prior immigration history”.
ICE has not given details about the nationality 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.