A darkening outlook for companies from banks to retailers to energy producers pummeled Wall Street, sending the Dow Jones industrials down nearly 250 points, or 2.94 per cent, and giving the other major indexes a loss of 3 per cent.

The plunge leaves the Dow and the broader Standard & Poor's 500 index down more than 9 per cent in six sessions. The S&P 500, the gauge tracked by professional investors, has now given up half its gains since it closed at an 11-year low on Nov 20.