The KOSPI fell more than 8 percent during trading, triggering a circuit breaker on the main KOSPI market. Large semiconductor shares including Samsung Electronics and SK Hynix slid sharply, while selling by foreign investors and institutions dragged the index lower.

The Korea Exchange said on July 7 it activated a circuit breaker that temporarily halted trading on the KOSPI market at 1:51:34 p.m. It was the sixth activation this year.

At the time, the KOSPI was down 646.85 points, or 8.03 percent, from the previous session, at 7,404.48.

A circuit breaker is a market-stabilisation measure that is triggered when the KOSPI stays down 8 percent or more from the previous close for at least 1 minute. Once triggered, all trading on the KOSPI market is suspended for 20 minutes.

Orders are then accepted for 10 minutes before trading resumes through a single-price auction.

By investor type, foreigners and institutions were net sellers of 3.35 trillion won and 220.4 billion won, respectively. Retail investors were net buyers of 3.51 trillion won, absorbing the selling.

Among the largest stocks by market capitalisation, chipmakers posted the biggest declines. As of 1:59 p.m., Samsung Electronics was trading at 287,000 won, down 9.75 percent from the previous session. SK Hynix fell 10.58 percent to 2,095,000 won.