While the surge came as a relief to many, Wall Street professionals warned that more rough days lie ahead, in part because of weakness in China, where signs of an economic slowdown triggered the sell-off that has shaken global markets over the past week.

More than US$2 trillion has been erased from American equity values since the S&P 500 started its losing streak, breaking a calm in a stock market that had gone nearly four years without a 10 percent correction.

The broader Standard & Poor’s 500 index jumped 72.90 points, or 3.9 percent, to 1,940.51.

Elsewhere in Asia, Australian shares gained 0.7 percent to 5,170.90 and South Korea’s Kospi rose 2.4 percent to 1,891.63.

A rebound that took the Dow up more than 440 points on Tuesday disappeared in the final hour of trading, with investors giving in to trepidation over what would happen overnight in China.

The Shanghai gauge rallied for a second day on Friday amid speculation authorities were supporting equities before a World War II victory parade next week that will showcase China’s military might.

Both indexes posted their biggest one-day percentage gains in almost two months. China’s key share indexes also ended down after attempts to move higher were slapped back by waves of selling several times, reflecting hopes for more government and central bank support.

As Fed officials prepare for their annual meeting in Jackson Hole, Wyoming, “people are looking for insight on what’s really going to happen on interest rates”, said trader Andrew Sullivan at Haitong Securities in Hong Kong.

In corporate news, Pepco Holdings Inc (POM.N) fell 16.47% after a District of Columbia regulator denied Exelon Corp’s $6.8 billion bid for the power utility, possibly delivering a knockout blow to the deal.

Energy stocks were among the biggest gainers as oil climbed back above $40 a barrel.

The Fed’s rate-setting committee is scheduled to meet next on September 16. While the Shanghai Composite retreated another 1.3%, Japan’s stock market soared 3% and European markets held steady after Tuesday’s big gains.

Chinese stocks bounced around Wednesday before ending weaker for the fifth day running.

Money has been steadily flowing out of US funds in recent weeks, the ICI reported.

The FTSE 100 in London tumbled 1.5 percent after the opening bell, while Germany’s DAX lost 1.3 percent, and continues to flirt with bear market territory.

Copper was up about 3.8 percent, moving further away from Monday’s six-year low.

In currency markets, the dollar rose to 120.18 yen from Wednesday’s 120.14 yen. The euro climbed to $1.1261 from $1.1242.

Benchmark U.S. crude gained $1.28 to $39.88 in electronic trading on the New York Mercantile Exchange.