Mumbai: The BSE benchmark Sensex on Tuesday, fell 204 points to a five-week low of 18,109.89 on selling of real estate, banking and IT stocks by funds, jittery over a slowing domestic growth amid nagging concerns over a bumpy US economic recovery.

Sensex, which had gained 117 points on Monday, tumbled 204.44 points to 18,109.89, its lowest since June 23, after the Prime Minister's Economic Advisory Council lowered the country's economic growth forecast to 8.2 percent this fiscal from earlier estimate of 9 percent.

Investors sought to book profits to avail of yesterday's rally, which along with a weak Asia trend and lower opening in Europe after the US posted weak factory output pulled down the Bombay Stock Exchange's 30-share Sensex.

However, Sensex leader Reliance Industries that perked up by 0.51 percent partly capped the losses.

IT exporters bore the brunt of the uncertainty over the US economic recovery as they get more than 50 percent of their revenue from exports to the US and Europe.

IT index tumbled 1.50 percent as Infosys –industry bellwether and Sensex's second most weighted scrip-- tumbled 2 percent while larger rival TCS slipped 0.26 percent. Wipro, the third-biggest Indian software company, slid 2.37 percent.

Realty sector index slid the most at 2.09 percent, followed by metal index that fell 1.83 percent, and banking index at 1.71 percent.

Broad-based National Stock Exchange's 50-scrip index Nifty fell 60.25 points to below 5,500 points level at 5,456.55 on decline in IT, banking and interest rate- sensitive sectors stocks.