SEOUL, July 28 (Xinhua) -- South Korea's bourse operator on Tuesday triggered a circuit breaker on the KOSPI after activating sell sidecars on both the KOSPI and KOSDAQ markets amid big tech sell-offs.
The benchmark KOSPI plunged 543.49 points, or 8.04 percent, to trade at 6,212.26 as of 10:16 a.m. local time (0116 GMT), while the smaller KOSDAQ tumbled 50.03 points, or 6.54 percent, to 714.83.
The KOSPI opened 5.26 percent lower and extended losses in the morning session, leading to the activation of sell sidecars on both the KOSPI and the KOSDAQ in early trading.
The sidecars are issued to temporarily restrict program trading to cool down sudden futures market volatility.
A level 1 circuit breaker was activated on the KOSPI after the index sustained a loss of over 8 percent for more than one minute.
The circuit breaker is issued in stages when the KOSPI or KOSDAQ dives by 8 percent, 15 percent and 20 percent.
The first two stages halt trading for 20 minutes, followed by a 10-minute single price auction, while the final stage instantly shuts down the market for the day.
The South Korean stock market suffered a meltdown amid escalating geopolitical tensions in the Middle East, which fanned inflation fears as global oil prices surged.
Concerns re-emerged over U.S. interest rate policies and massive tech-led sell-offs, accelerating the panic selling in heavyweight semiconductor shares such as Samsung Electronics and SK hynix.
Samsung Electronics and SK hynix dropped 9.45 percent and 11.01 percent each, driving the overall market rout. ■