South Korean stocks plunged, imperiling the world’s biggest rally, as investors pulled back from artificial intelligence bets that have fueled the bull market in global equities.

Memory chipmaker shares led a rebound in South Korean stocks, demonstrating investors aren’t quite ready to throw in the towel on the artificial intelligence boom.

South Korea’s $4.9 trillion stock market is starting to flash signs of strain after a world-beating rally.

South Korea’s stock market lurched from one extreme to another for a third straight session Wednesday, extending a stretch of swings that has whipsawed investors and repeatedly triggered market safeguards.

The breakneck surge in memory-chip stocks is intensifying, sending the market capitalizations of SK Hynix Inc. and Micron Technology Inc. above $1 trillion for the first time, as investors bet the AI boom will lead to a sustained revaluation of the industry.