The Bombay Stocks Exchange benchmark Sensex rose by over 116 points to cross the psychological 20,000-mark in opening trade today. The Sensex was trading at 20,000, up by over 111 points a short while ago. Analysts said the rise in Sensex is due to a firming trend in the Asia region. Meanwhile, Hong Kong's Hang Seng index was up by 0.45 percent and Japan's Nikkei gained 0.59 per cent in early tradetoday.