The White House phoned Hyundai chief executive José Muñoz personally to apologize for a massive immigration raid at a battery factory in the U.S. state of Georgia, the CEO said on November 19.

BBC News reports that, speaking at a conference of business leaders in Singapore, Muñoz said the governor of Georgia had also called him and said, "I don't know what happened, this is not state jurisdiction."

In September, more than 300 South Korean workers were detained in a raid at a battery plant operated by Hyundai and electronics giant LG, raising tensions between Washington and Seoul.

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The New York Times reported November 13 that the ex-detainees are preparing a class-action lawsuit against U.S. immigration authorities over their detention, which they claim was illegal because they had valid work visas. They also claim the detention center to which they were sent was “unsanitary.”

Meanwhile, The U.S. State Department has reissued work visas for some of the South Korean workers.

Muñoz said during a panel discussion at the Bloomberg New Economy Forum November 19 that he believed that someone had "made a phone call and made it look like there were illegal immigrants" at the plant. "That's absolutely not the case," he said.