South Korea's stock market extended its losing streak to a third consecutive session on Thursday, as better-than-expected earnings from tech giant Samsung Electronics failed to soothe investor jitters, and the government unveiled fresh measures to curb demand for leveraged exchange-traded funds (ETFs).

The benchmark Kospi index declined by 1.1%, adding to a cumulative 16% plunge over the prior two trading days. Despite reporting a second-quarter profit surge of more than 250 times, shares of Samsung Electronics still fell by 1%. Meanwhile, memory chip rival SK Hynix saw its stock drop by 6%.

Senior officials from South Korea's Ministry of Economy and Finance, the Bank of Korea, and financial regulators held an emergency meeting on Wednesday evening, pledging to implement additional measures to stabilize the market. These new rules specifically target retail investor participation in leveraged ETFs, following a two-day market rout that resulted in billions of dollars in investor losses.

The finance ministry stated that the new restrictions include limiting the maximum proportion of leveraged ETFs within an individual investor's overall portfolio and raising the associated transaction costs. Kim Dojoon, CEO of Zian Investment Management, commented that while these measures might help reduce market volatility in the future, they are unlikely to halt the current downward momentum immediately. "The core problem right now is that there are no buyers in the market. We need new buyers, whether it's a market stabilization fund stepping in to provide support. The most important thing is to signal to the market that there is still buying interest," he said.

The Kospi index has now fallen approximately 40% from its June peak, with losses accelerating this week as investors question the sustainability of the artificial intelligence (AI) trade boom. On Wednesday, the index triggered a circuit breaker for the second consecutive day, an unprecedented event that underscored the severity of the sell-off.