Korean shares were up sharply late Thursday morning as foreign investors turned to buying, one day after their massive selling led to a plunge in the local stock market.

The benchmark Korea Composite Stock Price Index added 19 points, or 0.97 percent, to 1,972.12 as of 11:20 a.m.

On Wednesday, the index closed 1.85 percent lower from the previous session as foreign investors ended their five-day buying streak and dumped 426.5 billion won ($369 million) worth of local shares.

As of 11:20 a.m. foreigners remained net buyers, purchasing a net 72.9 billion won, while institutions and retail investors offloaded a combined net 100.6 billion won.

An earnings surprise from the country's largest business, Samsung Electronics, helped boost investor sentiment.

The tech giant said its Q2 operating income was estimated at 8.1 trillion won, far surpassing the earlier market consensus of 7.32 trillion won.

Samsung Electronics spiked 0.99 percent, while most other large caps were also in positive terrain.

Leading automaker Hyundai Motor added 1.15 percent, while top portal operator Naver advanced 0.67 percent.

The local currency was trading at 1,156.30 won against the U.S. dollar, up 9.30 won from Wednesday's close. (Yonhap)