The Sensex at the Bombay Stock Exchange rose 125 points, or 0.7 per cent, to 18,644 in the first few minutes of trade, this morning, on renewed buying by investors at attractive lower levels. But later, in volatile trade, the Sensex gave up all its initial gains, to lose about 150 points at one stage. Still later, the benchmark index again rebounded, and stood 57 points, or 0.3 percent in positive territory, at 18,576, in afternoon deals, a short while ago.Elsewhere in Asia, the key benchmark indices in China, Hong Kong, Singapore, South Korea, and Japan were trading mixed, today. The US Dow Jones Industrial Average had ended 0.4 per cent higher in Friday's session.