Nasdaq plunges more than 3% as tech weakness returns

The tech-rich Nasdaq Composite Index dived more than three percent Thursday in afternoon trade as anxiety over pricey technology equities again pushed US stocks into the red.

Near 1920 GMT, the Nasdaq plummeted 131.56 (3.14 percent) to 4,052.34. The index got as low as 4,042.76 earlier in the session.

The Nasdaq has been exceptionally volatile over the last week, losing 2.6 percent last Friday before notching large gains on Tuesday and Wednesday.

Analysts say investors are worried that high-flying technology stocks like Facebook and Priceline may be overvalued. The biotechnology sector has also seen major swings during this period.

Meanwhile, the Dow Jones Industrial Average dropped 258.94 (1.58 percent) to 16,178.24, while the broad-based S&P 500 slumped 37.98 (2.03 percent) to 1,834.20.