Seoul shares tumbled by more than 3.5 percent on Friday as data fueled concerns over the US economy despite the Federal Reserve's rate-cut signals. The Korean won fell against the US dollar.

The benchmark Korea Composite Stock Price Index (KOSPI) plummeted 101.49 points, or 3.65 percent, to close at 2,676.19.

The KOSPI has fallen 2 percent this week.

Trade volume was heavy at 523.78 million shares worth 12.87 trillion won ($9.38 billion), with decliners far outnumbering gainers 868 to 58.

Institutions and foreigners sold a combined 1.62 trillion won worth of stocks, offsetting individuals' stock purchases valued at 1.61 trillion won.

Overnight, the Dow Jones Industrial Average fell 1.2 percent to 40,347.97 points, while the tech-heavy Nasdaq plunged 2.3 percent to 17,194.15.

US data showed unemployment claims hit the highest in almost a year and manufacturing shrank. The monthly employment data is set to be released Friday (US time).

The Fed signaled this week it is on course to cut its benchmark rates in September if conditions meet its forecast.

In Seoul, most large-cap stocks declined, with tech shares hit hardest. Battery and telecom stocks were among a few gainers.

Market bellwether Samsung Electronics fell 4.2 percent to 79,600 won, No. 2 chipmaker SK hynix Inc. plunged 10.4 percent to 173,200 won, top carmaker Hyundai Motor Co. shed 3.8 percent, and leading refiner SK Innovation Co. shed 2.7 percent to 104,300 won.

Among gainers, leading battery maker LG Energy Solution Ltd. rose 0.8 percent to 336,000 won, refiner S-Oil Corp. climbed 0.7 percent to 68,500 won, and Hybe, the K-pop powerhouse behind BTS, was up 3.1 percent to 180,800 won.

The local currency had been trading at 1,371.2 won against the dollar as of 3:30 p.m., down 6 won from the previous session. (Yonhap)