South Korean workers detained during a massive immigration raid in Georgia Thursday will be returned to South Korea on a chartered flight following negotiations, an official announced Sunday.

“Negotiations for the release of the detained workers have been concluded, after swift responses by the relevant ministries, business agencies, and companies,” said South Korean Presidential Chief of Staff Kang Hoon-sik.

“However, some administrative procedures remain, and once they’re completed, a chartered plane will depart to bring back our citizens,” he added.

The workers were among 475 detained Thursday during a large-scale immigration raid at the Hyundai Metaplant in Ellabell, Georgia, which houses an electric vehicle battery plant jointly operated by South Korea-based companies Hyundai and LG Energy Solution. About 300 of those detained are South Korean, officials said.

The South Korean government has been actively working to secure their release, along with the Korean Embassy in Washington, DC, and the Consulate General in Atlanta.

“To prevent a recurrence of similar cases, we will work together with the Ministry of Trade, Industry and Energy and the companies concerned, to review and improve the visa system and stay status of people traveling to the US for investment projects,” Kang said Sunday.

“The government will ensure that all necessary measures are effectively implemented to achieve both the swift release of our detained citizens and the stable implementation of the investment projects.”

South Korean President Lee Jae Myung previously called for “all-out necessary measures” to support the detainees.

This is a developing story and will be updated.