SINGAPORE – The South Korean government says it is investigating potential human rights violations during the raid and detention of Korean workers by US authorities.

South Korea has expressed "strong regret" to the US and has officially asked that its citizens' rights and interests are not infringed during law enforcement proceedings, said a presidential spokesperson on Monday.

More than 300 South Korean workers returned home on Friday after being held for a week following a raid at an electric vehicle battery plant in the US state of Georgia.

The incident has tested ties between the countries, even as South Korean firms are set to invest billions in America under a trade deal to avoid steep US tariffs.

South Korean authorities will work with the relevant companies to "thoroughly investigate any potential human rights violations or other issues", said the presidential spokesperson during a press briefing.

The BBC has contacted the US Immigration and Customs Enforcement (ICE) for comment.

The raid has raised tensions between the US and South Korea, where many of those detained were from, with President Lee Jae-myung warning that it will discourage foreign investment into the US.

He called the situation "bewildering", adding that it is a common practice for Korean companies to send workers to help set up overseas factories.

Last week, Hyundai said the plant's opening will be delayed by at least two months.

South Korea's trade unions have called on Trump to issue an official apology. – BBC