Asian stocks fell, with the regional benchmark index heading for its biggest weekly decline in a month, after global equities sank into a bear market and Japanese shares extended losses as the yen strengthened.

The MSCI Asia Pacific Index dropped 1.7 percent to 114.50 as of 9:11 a.m. in Tokyo. The gauge is headed for a 4.9 percent decline this week. The Topix index slipped 4.1 percent as the market resumed trading following Thursday’s holiday. Combined losses in U.S. and European equities dragged the MSCI All-Country World Index down 20 percent from a record reached in May, the common definition of a bear market.

Central bank activity remained in focus as negative interest rates have eclipsed investor worries over China’s fading economy and the near two-year collapse in oil prices. Sweden lowered interest rates that are already below zero, about two weeks after Japan shocked markets by imposing negative rates in a bid to quell the turmoil. Investors ignored a second day of testimony from Janet Yellen, whose indication that the Federal Reserve won’t rush to raise benchmark interest rates in the face of global ructions failed to stem the selloff in risk assets.

Futures on the Hang Seng Index slipped 1.4 percent in their most recent trading, while those for the Hang Seng China Enterprises Index lost 1.6 percent. Hong Kong stocks fell Thursday in their worst start to a lunar new year since 1994 as the global equity rout deepened. Markets in mainland China, Taiwan and Vietnam remain closed for the holidays.

Source: Bloomberg