Asian stock markets plunged Thursday as unexpected interest rate cut in South Korea fueled concerns over the global economic slowdown, while the Federal Reserve offered no strong hints of another round of quantitative easing.

The Bank of Korea (BoK) surprised the market by cutting its key policy rates for the first time in three years. After leaving it on hold for twelve consecutive meetings in a row, the BoK lowered its key policy rate by 25bp to 3 percent overnight and said it was a preemptive move.

“The central bank turned more pessimistic over the growth outlook for both the global and domestic economies. Easing inflation has provided some leeway for the central bank to ease, if needed. However, this rate cut does not necessarily imply a slew of rate cuts going forward,” said a note from Credit Agricole.

The rate cut was the first since February 2009 and followed a slew of rate cuts by major central banks over the past week. However, Central banks' actions to stimulate the global economy failed to calm market jitters and raised concerns among investors that the actions reflect a pessimistic outlook of policymakers on their economies.

“The global economy is deteriorating faster than central banks can ease policy. Your best bet is to hold on to cash,” Tomomi Yamashita, a senior fund manager at Shinkin Asset Management Co. told Bloomberg.

Meanwhile, the Federal Reserve released minutes from a recent meeting, dashing hopes of a fresh dose of quantitative easing (QE3) in the near future to bolster the fragile U.S. recovery.

The Fed Minutes noted that only a few members expressed the view that further policy stimulus would be necessary to promote satisfactory growth in employment and to ensure that the inflation rate would be the Committee's goal. Several others noted that additional policy action could be warranted if the economic recovery were to lose momentum.

Japanese shares plunged after the Bank of Japan decided to hold off on any major policy moves following a two-day meeting. Benchmark Nikkei declined 1.48 percent or 130.99 points to 8720.01. Exporter companies’ shares were hurt as the yen strengthened against major counterparts.

 Panasonic Corp. plunged 4.47 percent and Sharp Corp slumped 7.02 percent while Toyota Motor slipped 1.79 percent and Nomura Holdings fell 2.54 percent.

Hong Kong's Hang Seng plunged 2.03 percent or 394.76 points to 19,025.11 while Chinese Shanghai composite gained 0.46 percent. Financial and property developers led the declines in Hong Kong.

China Merchants Bank declined 2.34 percent and Agile Property Holdings slipped 2.21 percent while Chow Tai Fook Jewellery Group tumbled 8.78 percent.

Seoul shares tumbled after surprise rate cut by BoK. Benchmark KOSPI declined 0.17 percent or 3.06 points to 1826.39. Samsung Electronics declined 2.42 percent and Hyundai Motors plunged 3.10 percent.

Indian stock markets plunged, led by declines from IT shares, following weaker than expected first quarter results from nations second largest software services firm Infosys Technologies Ltd. Indian benchmark BSE Sensex plunged 1.51 percent or 264.49 points to 17224.65. Infosys tumbled 8.61 percent and Wipro Ltd. plunged 3.54 percent.