The Trump administration is still dealing with the international fallout caused by its recent arrest and detention of hundreds of South Korean workers during a raid on a battery plant in Georgia.

After the fierce backlash to the arrests and detention — in reportedly terrible conditions — of over 300 South Korean workers, President Donald Trump issued a statement on social media seemingly referring to the arrests and saying he didn’t want to “frighten off” investment in the United States. A top U.S. diplomat has also expressed “deep regret over the incident,” according to the South Korean government.

But the fallout continues.

South Korea is investigating potential human rights abuses experienced by the workers once they were placed in the custody of U.S. Immigration and Customs Enforcement last week, a spokesperson for South Korean President Lee Jae-yung said Monday. The workers have since returned to Korea on a plane sent to the United States by their government.

“I understand that the government is conducting a more thorough review with the companies to determine whether any human rights violations occurred,” presidential spokesperson Kang Yu-jung said in a press briefing, Yonhap News Agency reported.