Mumbai-Sensex at the Bombay Stock Exchange lost considerably more ground, and had slumped 240 points, or 0.8 percent, to 31,653 a short while ago. The Nifty at the National Stock Exchange had dropped 83 points, to 9,891.Stock markets have fallen across the globe also.After escalating geopolitical tensions, after North Korea said it had successfully tested a hydrogen bomb. So other key Asian markets in Japan, Hong Kong, South Korea and Singapore had declined about 1 percent, each.