US stocks have tumbled after an early rally faded amid market volatility over concerns about central banks’ stimulus plans.

At the closing bell on Wednesday, the Dow Jones Industrial Average was down a hefty 127.25 (0.84 per cent) at 14,994.77, the third straight day of blue-chip losses.

The broad-based S&P 500 slid 13.59 (0.84 per cent) to 1612.54, while the tech-rich Nasdaq Composite Index lost 36.52 (1.06 per cent) at 3400.43.

“There isn’t any continuity to the market’s trading behaviour,” said Patrick O’Hare of Briefing.com.

“The inconsistency can be blamed on the Federal Reserve and other central banks, which have scrambled their policy communications just enough to keep everyone guessing as to what comes next.”