As the KOSPI gave up the 5000 mark and a sidecar (sell sidecar) was triggered for the third time in a week on the 6th, the index is displayed on the electronic board in the Hana Bank dealing room in Jung-gu, Seoul. Seong Dong-hoon reporter

Amid anxiety sparked by artificial intelligence (AI), the KOSPI plunged by more than 5%, triggering a sell sidecar (a temporary halt of program-trading sell orders) on the 6th.

The Korea Exchange announced at 9:06 a.m. that a sell sidecar had been triggered on the main board. A sell sidecar suspends program selling for five minutes to mitigate volatility. It is triggered when KOSPI 200 futures remain down 5% or more from the previous close for one minute. This was the first sell sidecar in four days, since the 2nd, when the KOSPI plunged more than 5%.

As of 9:23 a.m., the KOSPI was trading at 4899.30, down 264.27 points (5.12%) from the previous session, swiftly breaking below the 4900 level. Large-cap index heavyweights including Samsung Electronics (-3.45%), SK Hynix (-5.23%), and Hyundai Motor (-5.53%) fell sharply across the board, dragging the index lower.

The KOSDAQ also plunged more than 5% intraday, giving up the 1100 level during the session.

The exchange rate also moved higher amid net selling by foreign investors in the domestic stock market and risk-off sentiment. In the Seoul foreign exchange market, the won·dollar rate opened at 1472.7 won, up 3.7 won, and immediately moved above the 1470-won level.

Worsening U.S.-driven anxiety, including a sharp drop in U.S. technology stocks amid concerns about tech industry business models, is acting as a headwind for the domestic market, which had risen steeply.