The Nasdaq Composite, which tracks the country's largest tech firms, plunged 3.4% at the opening bell. The Dow fell 180 points and the S&P 500 tumbled nearly 2%.

China's DeepSeek, which released an open-source artificial intelligence model in December, claimed that it took only two months and less than $6 million to create — far less than the billions invested by U.S. tech giants.