An electronic board showing the Korea Composite Stock Price Index at a dealing room of the Hana Bank headquarters in Seoul on Wednesday. (Yonhap) Seoul shares plummeted 5.4 percent Wednesday as technology stocks extended their losses and investors reassessed the outlook for artificial intelligence trade. The Korean won rose against the US dollar.After opening 2.7 percent lower, the benchmark Korea Composite Stock Price Index extended losses to close down 409.52 points, or 5.4 percent, at 7,246.79.Trade volume was heavy at 495.75 million shares worth 41.65 trillion won ($27.78 billion), with decliners outnumbering gainers 763 to 124.Foreigners bought a net 335.64 billion won worth of stocks, while institutions and foreigners sold a net 337.7 billion won and 45.1 billion won, respectively.Most of large-cap stocks declined, tracking overnight losses on Wall Street. The Dow Jones Industrial Average fell 0.25 percent, while the tech-heavy Nasdaq composite declined 1.16 percent.An extended decline in Korean stocks was driven by investor concerns that rising capital spending and expanding production capacity at major technology companies may take longer to generate the earnings growth needed to justify their elevated valuations, analysts said.In Seoul, tech stocks led the decline.Market bellwether Samsung Electronics plunged 6.25 percent to 277,500 won, while chip giant SK hynix declined 5.68 percent to 2,076,000 won.Top carmaker Hyundai Motor dropped 3.55 percent to 462,500 won, and defense company Hanwha Aerospace shed 7.22 percent to 1,041,000 won.Among gainers, shipping firm HMM rose 2.3 percent to 20,050 won, and S-Oil climbed 3.3 percent to 131,600 won.The Korean won was trading at 1,498.5 won per US dollar as of 3:30 p.m., up 29.7 won from the previous session. (Yonhap)