NEW YORK, March 12 — Trading on Wall Street’s three main indexes was halted moments after the opening bell today as the S&P 500 slipped seven per cent, setting off an automatic 15-minute cutout, for the second time this week.

At 9.35am ET the Dow Jones Industrial Average was down 1,696.31 points, or 7.20 per cent, at 21,856.91, the S&P 500 was down 192.33 points, or 7.02 per cent, at 2,549.05 and the Nasdaq Composite was down 558.80 points, or 7.03 per cent, at 7,393.25. — Reuters