By Jiyoung Sohn and Ryan Felton

Nearly 500 people were arrested as part of an immigration raid at a Hyundai Motor battery plant under construction in Georgia as part of a criminal investigation into employment practices at the site, a Homeland Security official said Friday.

The operation Thursday resulted in the arrest of 475 individuals, the majority of whom were South Korean nationals, said Steven Schrank, a special agent in charge of Homeland Security investigations in Atlanta.

Those arrested had illegally crossed the border, entered through a visa waiver program that prohibited them from working or had overstayed their visas, Schrank said at a press conference Friday morning.

"This was the largest single site enforcement operation in the history of Homeland Security investigations," Schrank said

No criminal charges were filed as of Friday, he said, and the investigation remains ongoing.

"Those who exploit our workforce, undermine our economy, and violate our federal laws will be held accountable," Schrank said. Schrank said the government's investigation has been ongoing for months.

The carmaker has pledged $26 billion in U.S. investments in recent weeks.

South Korea protested the action to the U.S. and said it was trying to secure the release of its citizens.

"This was not an immigration operation where agents went into the premises, rounded up folks and put them on buses," Schrank said. "This has been a multi-month criminal investigation where we have developed evidence, conducted interviews, gathered documents, and presented that evidence to the court in order to obtain a judicial search warrant."

A search warrant in the case was issued Aug. 31, according to a court filing. The government filed a motion to unseal a redacted version of the warrant Friday, and a judge granted the request. A copy of the warrant wasn't immediately available.

Investigators are continuing to look at which company employed each of the individuals, Schrank said, but he noted a network of subcontractors worked at the site.

The raid and arrests come after months of tense negotiations between the U.S. and South Korea over tariffs and investment. In late July, the two countries agreed that a 15% tariff rate would be imposed on South Korean imports in exchange for South Korea investing $350 billion in the U.S.

The factory is being built by a joint venture between South Korea-based Hyundai Motor and a South Korean battery manufacturer, LG Energy Solution. The plant is located in the town of Ellabell, near Savannah, Ga., and is part of a $7.6 billion Hyundai complex that the state has described as the largest manufacturing project in Georgia's history.

The plant, once completed, is set to supply batteries to Hyundai Motor's nearby electric-vehicle manufacturing plant, which opened last year. Hyundai has pledged to employ 8,500 people there by 2031 as part of a $2 billion incentive package it received from Georgia.

Among those detained at the factory were South Korean employees of LG Energy Solution on business travel. Hyundai Motor said it believed that it didn't directly employ any of those detained. LG Energy said Friday it was cooperating with the South Korean government and relevant authorities to ensure the employees' safety and secure their prompt release from detention.

The joint venture said it was cooperating with authorities and paused construction.

South Korea's Ministry of Foreign Affairs on Friday expressed regret at the detention of Korean nationals at the Georgia site and said it had conveyed its concerns to the U.S. Embassy.

"The economic activities of our investing companies and the rights and interests of our citizens must not be unjustly infringed during the process of U.S. law enforcement," the ministry said.

South Korean companies in strategic industries including semiconductors, shipbuilding and batteries have pledged tens of billions of dollars in new investments in the U.S.

The Hyundai raid could raise concerns for South Korean companies that are sending Korean personnel to the U.S. and hiring locally for their plants, said Hur Jung, an economics professor who studies international trade at Sogang University in Seoul.

If such crackdowns are repeated, it "would damage trust and hurt industrial cooperation between the U.S. and South Korea across various industries, with negative repercussions for local communities as well," said Hur, who is also president of the Korean Association of Trade and Industry Studies.

In August, Hyundai Motor announced it would increase its U.S. investment to $26 billion through 2028, up $5 billion from its earlier pledge. Around the same time, South Korean President Lee Jae-myung met President Trump for their first summit.

In addition to Hyundai Motor, Samsung Electronics is expanding chip-making facilities in Texas while SK Hynix is planning an advanced chip-packaging plant in Indiana. South Korean battery makers, including LG Energy Solution, Samsung SDI and SK On, have invested billions of dollars in building and operating U.S.-based factories across the Midwest.

South Korea is a partner in the Trump administration's push to "Make America Shipbuilding Great Again," and recently promised to spend $150 billion to help the U.S. revive its ship manufacturing, which has fallen far behind China.

Write to Jiyoung Sohn at jiyoung.sohn@wsj.com and Ryan Felton at ryan.felton@wsj.com

(END) Dow Jones Newswires

September 05, 2025 11:22 ET (15:22 GMT)

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