ANKARA 

South Korea said Monday that it is closely looking into whether any human rights violations took place during the raid and detention of Korean workers by US immigration authorities in Georgia earlier this month, local media reported.

"I understand that the government is conducting a more thorough review with the companies to determine whether any human rights violations occurred," Yonhap News Agency cited presidential spokesperson Kang Yu-jung as saying.

Over 300 South Korean nationals returned home Friday after a week in detention following the raid by US Immigration and Customs Enforcement (ICE) at a Hyundai-LG battery plant construction site in Bryan County following negotiations between the two countries.

Many workers spoke of cramped spaces, mold-covered mattresses, cold temperatures and limited access to basic hygiene at the detention center.

Several others described how they were shackled with chains around their waist, legs and wrists during the arrest and treated roughly by immigration officers.

"The Foreign Ministry is looking at whether our demands were properly addressed, and the companies are also conducting their own reviews to check whether any measures were insufficient on either the Korean side or US side," Kang said.

South Korea stressed that the rights and dignity of its citizens must not be unfairly violated, expressing strong regret to the US over the incident.

Washington has expressed "deep regrets" over the matter.

"Some of our requests have been accepted, and there were improvements. However, we will continue to look into whether any issues or inconveniences for our citizens remain," Kang added.