Raids spanning seven cities, six work sites and five companies ended in arrests for 680 people — and underscored an industry’s reliance on foreign-born workers at a time when federal immigration policy is the focus of intense debate.

On Aug. 7, U.S. Immigration and Customs Enforcement officers swept through agricultural processing plants in Mississippi, capping a year-long investigation. Officials said it was the largest single-state workplace enforcement action in U.S. history.

Mississippi is the fifth-largest chicken-producing state in the United States, and two of the raided companies, Koch Foods and Peco Foods, are among the nation’s biggest chicken producers.

The state’s poultry industry has a complex history with labor, race and immigration, academic research shows. The civil rights and worker rights movements of the 1960s and 1970s led to not only integration but also an exodus of white workers. By the 1990s, businesses began aggressively recruiting Latin American immigrants to fill their labor needs, luring them to rural Mississippi from places such as El Paso and Miami.

One company, since acquired by Koch Foods, dubbed the campaign the “Hispanic Project,” which resulted in a 1,000 percent increase in Scott County’s Latino population, where two of the raided plants are located, in a decade.

Angela Stuesse, a University of North Carolina at Chapel Hill professor who researched the Hispanic Project, said the undocumented immigrants who have worked at these plants long term stayed because they felt safe from crime and from ICE.

“The last 20 to 30 years has led to a real diversification of where immigrants go to find work,” she said. “It’s increasingly not in the traditional receiving communities in urban areas.”

But Marc Perrone, president of the United Food and Commercial Workers International Union, said the immigrants in the raided plants that the union represents now live in fear.

“Workers across this country are too scared to stand up for their rights and to report wage theft, dangerous work conditions and other workplace issues,” Perrone said in a statement to The Washington Post. “We urge the President and Congress to work together to fix our country’s broken immigration system, and to honor the due process that these workers and their families deserve.”

The raids come almost two months after a largely unfulfilled promise by President Trump to arrest and deport millions across the country as part of his administration’s zero-tolerance approach to the increasing numbers of Central American families attempting to cross the U.S.-Mexico border. In Mississippi, a nightmare for immigrant families turned into reality. Children of detained employees came home from their first week of school to empty homes and missing parents. As of Thursday night, a little more than half of the 680 detained workers were still in ICE custody.

Elizabeth Iraheta, 49, a U.S. citizen from El Salvador who works at the Koch Foods plant in Morton, took home the 12-year-old daughter of one of her co-workers who was arrested.

“We came here to work, and [the agents] are not looking for criminals,” Iraheta said in Spanish. “They’re looking at work sites for people who came to this country to work, who came to fight for their family.”

Privately held Koch Foods makes chicken products under its own brand and through private labels for buyers such as Walmart. The company is headquartered near Chicago and has no relation to the multinational Koch Industries. It employs nearly 13,000 people in Mississippi, Alabama, Georgia, Tennessee, Illinois and Ohio. Its Morton, Miss., plant produces more than 700,000 tons of poultry feed each year.

Its owner, Joseph Grendys, is worth $3.3 billion, Forbes estimates.

Koch Foods did not respond to requests for comment, but the company said in a release posted to its website Thursday that it uses E-Verify.

“Koch’s Morton facility, which employs more than 1,000 people, did not operate during the first shift today and is trying to determine how many employees were detained by federal authorities,” the statement read. “The company intends to continue to operate all shifts at the facility and minimize customer impact.”

This isn’t the first time the company has come under federal scrutiny because of its Morton plant. Last year, the company agreed to pay a $3.75 million settlement to Hispanic workers who alleged that they were discriminated against based on race, sex and national origin. The federal lawsuit was picked up by the Equal Employment Opportunity Commission and filed in 2011.

“EEOC alleges that supervisors touched and/or made sexually suggestive comments to female Hispanic employees, hit Hispanic employees and charged many of them money for normal everyday work activities,” an EEOC release reads. “Further, a class of Hispanic employees was subject to retaliation in the form of discharge and other adverse actions after complaining.”

Under the terms of the settlement, the company was required to create a 24-hour bilingual hotline to receive complaints of discrimination, and implement and publicize anti-discrimination training and policies at the plant in English and Spanish.

Caitlin Berberich, an attorney at Southern Migrant Legal Services in Nashville, represented 10 employees at the Morton plant in the lawsuit, which was settled in July 2018. She said she has been in touch with her clients in Morton that may have been affected by the raid.

“I do think that the timing is suspicious, given some of the statements that the U.S. attorney has made of when these investigations started,” she said.

In 2016, the U.S. Department of Labor’s Occupational Safety and Health Administration issued more than $88,000 in penalties to Koch Foods for nine safety violations that resulted in “severe worker injuries” at its Mississippi plant, according to an agency release.

And a U.S. Department of Agriculture investigation found “evidence of unjust discrimination” by Koch Foods against black farmers in Mississippi, who alleged that the company used its market power to harm their businesses starting in 2010. As of June 2019, Koch Foods had not been penalized, ProPublica and the Clarion-Ledger reported.

Peco Foods, based in Tuscaloosa, Ala., has been family-owned for three generations, according to its website. Mark Hickman runs the company his grandfather founded in 1937. The company operates five Mississippi plants, including the Canton, Bay Springs and Sebastopol facilities targeted by ICE agents. It also has operations in Arkansas and Alabama.

“We are fully cooperating with the authorities in their investigation and are navigating a potential disruption of operations,” the company told The Washington Post in a statement.

It also said it uses E-Verify, a federal program used to screen the employment eligibility of new hires through the Department of Homeland Security and the Social Security Administration.

Peco Foods settled a $9,550 penalty from the Occupational Safety and Health Administration in 2015 and has been investigated by the agency five more times since. In 2008, several employees accused the company of violating the Fair Labor Standards Act by denying overtime pay and “requiring them to perform ‘off the clock’ work.” Court records show that the company settled in 2012.

Three other small poultry processing plants were targeted in Wednesday’s raids. Heather Carrillo, who said she works at the PH Food office, said 80 employees at the poultry-processing plant in Morton were detained in the raid. It’s the business’s only location and uses E-Verify in hiring, she said.

Pearl River Foods opened its $2 million Carthage processing plant for the local poultry industry in 2017 and had created 600 jobs within a year, according to a news release. The business writes Facebook posts in English and Spanish and was recognized for its hiring with an economic development award given to the state in June. It did not respond to requests for comment.

MP Food’s processing plant in Pelahatchie also did not respond to requests for comment.

Stuesse pointed out that public companies operating poultry plants in some of the same Mississippi towns that were raided were unaffected.

“I think it’s possible that the Trump administration wanted to make a big show of being hard on immigration, but wanted to make sure the economic fallout didn’t hit the pocketbooks of the shareholders,” she said.

Matthew Albence, ICE’s acting director, said the companies could be charged with knowingly hiring undocumented workers and have their finances scrutinized. Mississippi law requires all employers in the state to use E-Verify.