South Korea's Kospi 200 plunges 8.1%, triggering trading halt

South Korea's Kospi 200 stock index fell 8.1% on Oct. 15, 2026 to a six-month low. Circuit breakers, automatic pauses after sharp drops, halted trading. Chipmakers SK Hynix and Samsung fell about 11% and 9.5%. The drop came amid a wider sell-off in AI-linked shares over US inflation and AI-sector debt fears.