The Sensex gained almost 120 points in opening trade on the Bombay Stock Exchange today. The Sensex was trading at 18,648, up by over 141 points a short while ago.Brokers said the availability of several stocks at attractive levels and a fall in food inflation provided much needed support to the market.In addition, covering-up of pending short positions byspeculators also supported the rally in the market, they said.In the Asian region, Hong Kong's Hang Seng index was up by 0.48 per cent, while Japan's Nikkei index remained almost flat in early trade today.The US Dow Jones Industrial Average ended 0.24 per cent higher in yesterday's trade.