In Stock market, the Sensex at the Bombay Stock Exchange plunged 460 points, to 24,946, a short while ago, on across-the-board selling by investors. The Nifty at the National Stock Exchange had slumped 146 points, to 7,595 a short while ago.The Chinese market sank more than 7 percent within the first thirty minutes of trading, and trading was halted for the rest of the day for the second time this week. This was the shortest trading day in Chinese stock market history. Stock markets in Japan, Hong Kong, South Korea and Singapore had been beaten down by between 1.1 percent and 2.9 percent. Brent crude oil futures dropped more than 3 percent, to 33 dollars per barrel. And at the forex market, the rupee had depreciated 10 paise, to 66.92 against the dollar in early trade.