U.S. stock indexes plunged in midday trading Thursday, echoing losses on European and Asian markets.

The Dow Jones Industrial Average of 30 key stocks is off 3.6 percent, with the broader S & P 500 down 4.1 percent. The technology-heavy NASDAQ index is down 4.4 percent.

Stocks closed sharply lower in Europe.

London's Financial Times index dropped 4.5 percent to close at 5,092. The CAC-40 in Paris fell 5.5 percent to end at 3,076. The DAX index in Frankfurt ended down 5.8 percent to finish the day's trading at 5,603.

In Asia, Tokyo's Nikkei index lost one and one-quarter percent to finish at 8,944.

Hong Kong's Hang Seng index slumped 1.3 percent to finish the day's trading at 20,016.

Gold is trading up $28.25 at $1,819.50 an ounce.

The dollar is trading higher against the euro, but down against the yen.