South Korea's KOSPI fell on Wednesday as heavy selling by foreign investors pushed it down to the 8,600 level. Semiconductor heavyweights such as Samsung Electronics and SK Hynix fell in tandem, leading the drop. The KOSDAQ, however, rose more than 2 percent, moving in the opposite direction to the KOSPI.

The KOSPI closed down 162.08 points, or 1.84 percent, at 8,639.41. It opened down 177.67 points, or 2.02 percent, at 8,623.82, narrowed losses and then weakened again.

By investor type, individuals and institutions were net buyers of 5.01 trillion won and 1.81 trillion won, respectively. Foreigners were net sellers of 6.95 trillion won, extending their selling streak to 19 sessions and weighing on the index. Individuals and institutions absorbed large foreign selling of nearly 7 trillion won on the day, but it was not enough to prevent the decline.

Most of the top market-cap stocks fell. Samsung Electronics fell 2.50 percent to 351,500 won and SK Hynix dropped 2.63 percent to 2,298,000 won.

Hyundai Motor fell 3.98 percent, Samsung Electro-Mechanics dropped 5.35 percent, LG Energy Solution lost 4.63 percent, Samsung Life fell 8.75 percent and HD Hyundai Heavy Industries slid 3.27 percent.

SK Square rose 1.11 percent and Samsung C&T climbed 10.20 percent.

The KOSDAQ rebounded for the first time in 6 sessions. It closed up 23.70 points, or 2.31 percent, at 1,049.73. Bargain-hunting buying appears to have flowed into the KOSDAQ, which had been relatively sluggish in a recent large-cap-led market centered on KOSPI heavyweights.

The market was marked by diverging moves in the KOSPI and KOSDAQ. The KOSPI was pressured by foreign selling and weakness in large semiconductor stocks, while the KOSDAQ ended higher despite intraday volatility. Whether funds that had recently concentrated in large caps shift partly to the KOSDAQ is expected to be a key point to watch going forward.

In the Seoul foreign exchange market, the won was at 1,530.60 per dollar, up 4.80 won from the previous session.