This photo, taken Wednesday, shows the trading room of Hana Bank in Seoul as South Korean stocks plunged by more than five percent on tech stock losses. Photo by Yonhap

Seoul shares plummeted 5.4 percent Wednesday as technology stocks extended their losses and investors reassessed the outlook for artificial intelligence (AI) trade. The Korean won rose against the U.S. dollar.

After opening 2.7 percent lower, the benchmark Korea Composite Stock Price Index (KOSPI) 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 (US$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.