The Sensex at the Bombay Stock Exchange fell 193 points, or 1.2 per cent, to 15,496 in early trade, today, on profit-booking by investors after yesterday's big rally, amid worries about slowing domestic growth, and weak regional bourses. Later the Sensex remained weak, and stood 177 points or 1.1 per cent in the negative zone, at 15,508 in afternoon deals. Other key Asian markets in Japan, China, Singapore, Hong Kong, and South Korea were down by between 0.1 percent and 0.8 percent, amid a weakened growth outlook for China and Europe.