Asian stocks slid on Monday after soft Chinese factory surveys stoked global growth concerns, while the dollar edged back against the safe-haven yen as risk appetite waned.
MSCI's broadest index of Asia-Pacific shares outside Japan lost 0.6 percent.
Chinese stocks slipped in early trade, with Shanghai stocks dropping 0.7 percent and Hong Kong's Hang Seng down 1 percent.
State media reported police had arrested two executives from a Hong Kong-owned fund which allegedly pocketed millions of dollars from irregular futures trades.
China's factory activity fell for an eighth straight month in October, the Caixin purchasing managers index (PMI) showed, fuelling fears the economy may still be losing momentum in the Q4 despite a raft of stimulus measures.
The Caixin figures followed Sunday's official survey, which showed activity in China's manufacturing sector unexpectedly contracted in October for a third straight month.
Australian shares were down 1.4 percent and Tokyo's Nikkei retreated 1.7 percent.
"Global market worries triggered selling while the market was prone to profit-taking from last week's gains," said Hikaru Sato, a senior technical analyst at Daiwa Securities in Tokyo.
The dollar lost 0.2 percent to 120.435 yen as the fall in Tokyo shares cooled risk appetite and favoured the safe-haven Japanese currency. The dollar was already on the defensive after the BOJ on Friday wrong-footed investors who had wagered on the Japanese central bank easing policy and lifting the greenback.
With most central banks except the U.S. Federal Reserve committed to an easing bias, focus now falls on this week's run of U.S. data, including the all-important non-farm payrolls due on Friday, and how they could affect the Fed's stance on hiking interest rates.
The Fed did not hike rates last month but caused a stir by leaving the door open for a hike in December, again highlighting the divergence in monetary policies between the Fed and other central banks such as the European Central Bank and the BOJ.
"U.S. economic data bear significance for the December FOMC decision and could drive higher FX and rate volatility in the coming weeks," strategists at Barclays wrote.
"The October FOMC statement was somewhat more hawkish than our expectations, and with the assessment on global risk having been removed, we think there is a clear attempt by the FOMC to keep a December hike on the table."
The euro gained 0.3 percent to $1.1028, having risen against the green back Friday on a soft U.S. core personal consumption expenditure (PCE) index release.
The Australian dollar was firm at $0.7140.
In commodities, crude oil prices slipped, unable to sustain gains made on Friday on the latest decline in the U.S oil rig count. U.S. output may be declining but global supplies of crude and refined oil products continue to grow.
U.S. crude was down 0.5 percent at $46.36 a barrel.
Spot gold touched a 4-week low of $1,134.60 an ounce, hurt by lingering worries of a potential rate hike by the Fed. Higher interest rates tend to diminish the appeal of non-yielding bullion.