TOKYO (AP) -- Asian stock markets endured sharp losses Thursday as gyrations on the Tokyo market, the region's biggest, continued — fueled by worries about a surging yen and monetary policies in the U.S.
Investor skepticism about the economic strategies of Prime Minister Shinzo Abe for extracting Japan from two decades of stagnation also figured high in the Nikkei 225's big drop.
"The markets have been nervous for some time, and there was disappointment among some investors," said Katsuyuki Hasegawa, chief market economist at Mizuho Research Institute in Tokyo.
Japanese media reports said overseas hedge funds may be dumping Japan's equities following disappointment over the Bank of Japan's decision earlier in the week to refrain from additional monetary easing measures.
The Nikkei 225 index, which plunged more than 6 percent earlier in the day, was 5.3 percent down by midafternoon to 12,571.47.
Adding to the woes was the dollar's recent fall, trading at about 95 yen Thursday, in a reversal from 100 yen earlier. A cheap yen is a boon for Japan because it helps the nation's giant exporters by raising their overseas revenue when translated into yen.
Elsewhere, the Hang Seng index fell 2.9 percent to 20,731.52, while the Kospi in South Korea lost 1 percent to 1,891.10. Benchmarks in India, Indonesia, Singapore and Taiwan all fell 1 percent or more. Thailand's SET plummeted 5.2 percent.
Mainland Chinese were pummeled as accumulating signs of a slowdown in growth in the world's No. 2 economy caused investors to retreat. The Shanghai Composite Index slid 3.3 percent to 2,137.37 while the smaller Shenzhen Composite Index lost 3.1 percent to 952.76.
In April, the Bank of Japan announced a massive stimulus in an attempt to get inflation up to 2 percent. The euphoria that drove the Nikkei up to five-year highs has since dissipated and the index is now around 20 percent down from its recent peak.
The other major driver in markets has been the uncertainty over the future course of U.S. monetary policy following a solid, if unspectacular, improvement in economic data.
The markets now expect some reduction in the Federal Reserve's monthly asset purchases sometime this year. The stimulus has been one of the main reasons why many assets, such as global stock markets and emerging markets, have bounced back.
Analysts said markets will likely remain on edge until next week's Fed policy meeting for greater clarity on the timing and extend of any tapering.
"Risk appetite continues to shrink as the ongoing nervousness over Fed tapering continues to provoke significant position adjustments across markets," Mitul Kotecha of Credit Agricole CIB in Hong Kong said in a market commentary.
Among individual stocks, Apollo Tyres Ltd., an Indian company, plunged 19 percent after announcing plans to buy American tire maker Cooper Tire & Rubber for $2.5 billion.
Japanese exporters were battered because of the rising yen. Yamaha Motor Co. sank 7 percent. Bridgestone Corp. shed 5 percent. Olympus Corp. tumbled 7.5 percent.
On Wall Street, the Dow Jones industrial average fell 0.8 percent, to close at 14,995.23. The Standard & Poor's 500 index fell 0.8 percent to 1,612.52. The Nasdaq composite index fell 1.1 percent, to 3,400.43.
The euro rose to $1.3354 from $1.3331 late Wednesday in New York. The dollar fell to 94.40 yen from 95.71 yen.
Benchmark crude oil was down 59 cents at $95.29 per barrel in electronic trading on the New York Mercantile Exchange. The contract rose 50 cents to close at $95.88 on the Nymex on Wednesday.
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