The South Korean government said it is working to return its nationals who were detained in an immigration raid on a Hyundai facility in Georgia last week.

Federal and immigration agents conducted a massive sweep on the plant in Ellabell, Georgia, arresting 475 people as part of an investigation into allegations of unlawful employment practices. A South Korean spokesperson told NBC News that more than 300 of the arrests were South Korean nationals.

U.S. authorities, who had a search warrant, said the arrested workers were working or living in the country illegally.

South Korean President Lee Jae Myung’s office said Sunday that detainees will be returned to South Korea on a chartered flight. Hyundai did not immediately respond to CNBC’s request for comment.

Thursday’s raid, the latest in President Donald Trump‘s crackdown on illegal immigration, marked the Department of Homeland Security’s largest single-site enforcement operation in its history, according to Steven Schrank, special agent in charge of Homeland Security Investigations in Georgia.

White House border czar Tom Homan told CNN’s “State of the Union” on Sunday that the Trump administration would continue focusing on workplaces for immigration raids.

“We’re going to do more worksite enforcement operations,” he said. “These companies that hire illegal aliens, they undercut their competition that’s paying U.S. citizen salaries.”

The Georgia plant is home to South Korean companies Hyundai and LG Energy Solution, which are building a battery manufacturing plant together. The $7.6 billion Hyundai plant employs more than 1,200 people. The company began building its manufacturing plant in 2022 and started making electric vehicles less than two years later, making the plant one of the largest economic developments in the state.

LG Energy Solution said on Saturday that 47 of its employees were detained, along with an additional 250 people from “equipment partner companies.”

Schrank said the arrested workers were employed by contractors and subcontractors.

In a Friday statement, U.S. Attorney Margaret Heap said more than 400 agents took part in the raid.

“The goal of this operation is to reduce illegal employment and prevent employers from gaining an unfair advantage by hiring unauthorized workers,” Heap said in the statement. “Another goal is to protect unauthorized workers from exploitation.”

In a statement to NBC News on Friday, Hyundai said it was monitoring the situation and that none of the detainees were direct employees of the auto company.

The South Korean government said on Friday that it conveyed its “concern and regret” to the U.S. Embassy and urged them to ensure the South Korean employees’ rights were not violated.

“In the course of U.S. law enforcement, the economic activities of our investment firms and the rights and interests of our nationals must not be unjustly infringed upon,” said Lee Jae-woong, a spokesperson for South Korea’s foreign ministry.

In a Truth Social post, Trump wrote that he is calling on all foreign companies investing in the U.S. to “please respect our Nation’s Immigration Laws.”

“Your Investments are welcome, and we encourage you to LEGALLY bring your very smart people, with great technical talent, to build World Class products, and we will make it quickly and legally possible for you to do so. What we ask in return is that you hire and train American Workers,” he wrote.

Speaking to reporters on Sunday, Trump also said the raid had no connection to the economic ties between the two countries, saying that the U.S. has “a great relationship” with South Korea.

Hyundai told NBC News Monday morning that business travel to the U.S. remains in place, with some trips subject to internal review.