South Korean stocks marginally fell Thursday, snapping their two-day winning streak, as investors took profits amid lingering uncertainty over the United States' monetary tightening. The local currency fell against the US dollar.

The benchmark Korea Composite Stock Price Index lost 2.12 points, or 0.09 percent, to 2,481.52. Trading volume was moderate at 595.66 million shares worth 8.76 trillion won ($6.95 billion), with decliners outpacing gainers 508 to 363.

Institutions sold a net 384.86 billion won worth of shares, while retail and foreign investors bought a net 213.78 billion won and 148.18 billion won, respectively.

The index opened lower, tracking overnight losses on Wall Street, but bobbed in and out of positive terrain with a modest decline on individual and foreign buying.

"Hawkish comments from the Federal Reserve have weighed on sentiment, and investors moved to lock in profits from recent gains following a sharp drop of the Nasdaq Composite," Kiwoom Securities analyst Han Ji-young said.

On Wednesday, Fed Gov. Christopher Waller said he's "prepared for a longer fight to get inflation down" and interest rates need to remain high for some time. New York Fed President John Williams also said the US central bank needs to maintain "restrictive" rates for a few years to curb inflation.

Big-cap shared ended mixed.

Samsung Electronics inched down 0.16 percent to 63,000 won, and chip giant SK hynix fell 0.53 percent to 94,400 won.

Bio shares lost ground. Samsung Biologics fell 0.25 percent to 814,000 won and Celltrion skidded 0.84 percent to 165,600 won.

But leading battery maker LG Energy Solution grew 0.73 percent to 550,000 won, and Samsung SDI advanced 1.1 percent to 738,000 won.

LG Chem increased 1.19 percent to 68,000 won, and Posco Chemical surged 7.54 percent to 242,500 won.

Carmakers ended mixed, with top automaker Hyundai Motor shedding 0.06 percent to 172,600 won while its affiliate Kia going up 0.28 percent to 71,700 won.

Internet giant Naver decreased 0.22 percent to 230,000 won, while Kakao, the operator of the popular mobile messenger KakaoTalk, jumped 2.6 percent to 70,900 won.

The local currency ended at 1,260.4 won against the US dollar, down 0.3 won from the previous session's close. (Yonhap)