SEOUL Seoul said on Sunday that negotiations with the United States to secure the release of South Korean workers detained in a raid by U.S. immigration officials have been "concluded" and they would soon be freed and flown home. It follows the arrest of more than 300 South Korean workers at a Hyundai-LG battery plant being built in the southern state of Georgia on Sept. 4. The operation, carried out in the town of Ellabell, was the largest single site raid implemented so far under U.S.