SEOUL: South Korean shares fell 8 per cent on Tuesday, led by chipmakers, as investors questioned whether record earnings tied to AI could hold up.The benchmark KOSPI was down 646.85 points, or 8.03 per cent, at 7,404.48, as of 4.53am GMT (12.53pm, Singapore time). It triggered circuit breakers at 4.51am GMT, halting trading for 20 minutes.It was the sixth time circuit breakers were activated on the index this year during heightened volatility in semiconductor stocks, and the 12th time in history.Shares of Samsung Electronics dropped 9.75 per cent even after the chipmaker forecast a 19-fold jump in second-quarter operating profit from a year earlier, underscoring concern that strong results may already be priced in after a sharp rally in memory-chip stocks. "It is good news but can't be in