Concerns about an AI bubble send South Korean stocks plunging 4%.

South Korean stocks plunged more than 4% on Wednesday, continuing the trend of a sharp decline in Wall Street driven by concerns about overvaluation and an artificial intelligence bubble. The KOSPI index fell 135.79 points (3.29%) within the first 15 minutes of trading, dropping below 4,000 points again after more than a week of breaking through that level.