South Korean stocks plunged more than 10% on Tuesday, driven by a massive sell-off in technology shares amid growing doubts about the outlook for massive investments in artificial intelligence infrastructure. The South Korean won strengthened against the U.S. dollar.

The benchmark Korea Composite Stock Price Index (KOSPI) tumbled 732.09 points, or 10.84%, to close at 6,023.66 points, after briefly falling to 5,830.39 points during the session.

This marks the lowest closing level since the index ended at 5,967.75 points on April 14.

After opening 5.26% lower, the KOSPI continued to slide throughout the day, with losses exceeding 8% at one point in the morning. At 10:14 a.m. local time, the Korea Exchange triggered a circuit breaker, suspending trading in KOSPI-listed stocks for 20 minutes.

Trading volume was light, with 324.2 million shares worth 33.69 trillion won (approximately $23 billion) changing hands. Eight hundred and seventy-five stocks declined, while only 36 advanced.

Foreign investors sold 4.97 trillion won worth of local stocks on the day. Individual investors were net buyers of 4.33 trillion won, while institutional investors net purchased 630.1 billion won.

Seo Sang-young, an analyst at Mirae Asset Securities, said: "The sharp decline in the stock market today was not due to new negative factors, but rather a combination of issues that have been continuously discussed in the market and investor caution ahead of major tech companies' earnings season."

SK Hynix, the world's second-largest memory chipmaker, is set to report earnings on Wednesday, while Microsoft, Meta, and Amazon are scheduled to release results later this week.

Seo added that investors are looking for signs of potential returns from tech companies' massive investments in AI infrastructure.

In Seoul, the majority of stocks fell, led by declines in technology heavyweights.

Market bellwether Samsung Electronics tumbled 13.39% to close at 220,000 won, while SK Hynix fell 14.65% to 1.55 million won.

SK Square, the parent company of SK Hynix, fell 15.6% to 925,000 won. Leading chip equipment maker Hanmi Semiconductor dropped 12.22% to 179,500 won.

Hyundai Motor, South Korea's largest automaker, fell 9.68% to 364,000 won, while its affiliate Kia dropped 6.6% to 121,800 won.

Internet giant Naver declined 6.67% to 210,000 won, and Doosan Energy fell 8.74% to 64,700 won.

Major banking group KB Financial Group fell 4.29% to 165,200 won, while defense conglomerate Hanwha Aerospace dropped 2.67% to 875,000 won.

As of 3:30 p.m. local time, the won was trading at 1,462.5 against the U.S. dollar, strengthening by 6 won compared to the previous stock market close.