Nvidia's market value dropped more than $500bn after the emergence of DeepSeek - a low-cost chatbot built by a Chinese AI firm.

U.S. equity declines followed a selloff that started in Asia, with Japan's SoftBank Group finishing down 8.3%, and moved through Europe where ASML fell 7% ...

The S&P 500 dropped 1.7 per cent, and the Nasdaq 100 slipped 3.1 per cent. With big tech stocks crashing, US stocks were set ...