(LEAD) Seoul shares tumble over 4 pct on tech losses amid lingering AI concerns
South Korean stocks fell sharply on Thursday, with the KOSPI closing down 4.58% as tech shares, led by Samsung Electronics and SK hynix, suffered heavy losses. The decline was attributed to lingering concerns over AI profitability and losses in U.S. chip stocks, while the local currency rose and the Dow hit a record high.