Extending its initial gans, the Sensex at the Bomaby Stock Exchange surged 226 points, or 1.2 percent, to 18,584, in afternoon trade, a short while ago. Earlier in the morning, the Sensex had opened with a gain of 171 points, or 0.9 percent, at 18,529, on continued buying by funds and retail investors, fuelled by lower-than-expected wholesale inflation and falling global crude oil prices.Stock markets in China, South Korea, Hong Kong, Taiwan, Indonesia and Singapore had gained between 0.1 percent and 0.6 percent, today. But the US Dow Jones Industrial Average had plunged 1.8 per cent in yesterday's trade.