South Korean workers detained in a massive Immigration and Customs Enforcement (ICE) operation at a Hyundai plant in Georgia are set to be released, according to the South Korean government.

South Korean presidential chief of staff Kang Hoon-sik said on Sunday that the governments of South Korea and the U.S. have finalized a deal to release more than 300 South Korean workers who were detained on Friday during an ICE raid on Korean automaker Hyundai’s electric vehicle manufacturing site in Georgia.

The site has been lauded as the state’s largest economic development project.

Kang said there were still “administrative procedures” remaining to finalize the deal, but that a chartered plane would soon be sent to retrieve the Koreans in custody.

The Department of Homeland Security (DHS) said the raid on Friday detained 475 people, most of whom were Korean nationals. The raid was a result of a month-long operation into illegal hiring at the site, where Hyundai is teaming up with LG Energy Solution to manufacture batteries to power EVs.

Steven Schrank, the lead Georgia agent of Homeland Security Investigations, said the raid was the “largest single site enforcement operation” in the agency’s two-decade history, at a news conference on Friday.

The Associated Press contributed.