After U.S. Immigration and Customs Enforcement arrested nearly 700 potentially undocumented immigrant workers in Mississippi, more than 300 of those taken into custody were released on Thursday, according to Bryan Cox, an ICE spokesman.
"All persons released were transported back to their respective arrest locations," Cox said. "We took them all back to the plants where they were arrested. No one had to procure transportation to get themselves back."
"Preliminarily, it appears that approximately 30 detained aliens were released yesterday on humanitarian grounds at the individual sites where they were initially encountered, and another 270 detained aliens were released after being processed by HSI at the National Guard base in Pearl and returned to the place where they were originally encountered," the Department of Justice U.S. Attorney's Office, Southern District of Mississippi, said in a press release.
Immigration officials raided five Mississippi food processing plants Wednesday, arresting 680 mostly Latino workers in a move witnesses said came with "no warning."
The Immigration and Customs Enforcement raids, planned months ago, targeted seven plants belonging to five companies: Peco Foods, PH Foods Inc., Koch Foods, Pearl River Foods and A&B Inc.
Mexico's foreign minister, Marcelo Ebrard, said 107 Mexican nationals had been arrested in the raids, according to Reuters.
The raids happened hours before President Donald Trump visited El Paso, Texas, where gunman Patrick Crusius was charged with capital murder for a mass shooting that left 22 people dead and 26 injured.
Crusius is believed to have authored a racist and anti-immigrant screed, which was published via online message board 8chan before the shooting occurred.
The note cites the anti-immigrant, white supremacist Christchurch, New Zealand mosque shooter as an inspiration.
Heather Carrillo, 40, a PH Foods employee in Morton, told CNBC the officials came with "no warning" and that they treated everyone like they were the "lowest people on the face of the earth."
"You would think that somebody killed somebody the way they came and treated us," Carrillo said. "They didn't even put handcuffs, they put zip ties on everybody's hands."
She said about 60 officers came to the Morton location on Wednesday morning at 5:50 a.m., and arrested 90 people. They left the facility around 1:30 p.m.
"They said they had a federal warrant, and that we could corroborate or not, it didn't matter because they were going to take whatever they were going to take. Basically, just sit down and shut up," she said.
The workers at Koch Foods Inc. in Morton were taken to a military hangar to be processed for immigration violations. About 70 family, friends and residents shouted: "Let them go! Let them go!" according to AP.
Workers filled three buses, two for men and one for women, at Koch Foods Inc. in Morton, according to the Clarion Ledger. They were taken to a military hangar to be processed for immigration violations.
Acting ICE Director Matthew Albence told The Associated Press that the raids could be the largest such operation thus far in any single state. ICE did not return CNBC's requests for comment.
Immigration raids were common under President George W. Bush, including one at kosher meatpacking plant in Postville, Iowa, in 2008, which resulted in 400 arrests.
Peco Foods said in a statement, "We are fully cooperating with the authorities in their investigation and are navigating a potential disruption of operations."
Koch Foods said it planned to release a statement regarding the arrests, while Pearl River Foods, A&B Inc., and PH Foods did not immediately respond to requests for comment.