Mumbai: In sync with weakening global stock markets, the Bombay Stock Exchange benchmark Sensex on Friday tumbled nearly 529 points, or 4.05%, on selling by funds due to growing concerns that $700 billion rescue package by US would not be enough to halt global slowdown.

The BSE barometer index opened weak fell further to record a loss of 529.35 points at 12,526.32 as funds turned aggressive sellers in heavyweight stocks including market leader Reliance Industries and IT bellwether Infosys Technologies.

The key index dipped to a low of 12,472.61 points during the day.

The National Stock Exchange index Nifty also closed lower by 132.45 points, or 3.35%, at 3818.30 after falling to a low of 3804.85 during the day.

Marketmen said weak global trends dampened the domestic bourses. They said investors hold the view that America’s $700 billion package is not enough to revive the troubled credit and financial markets.

Heaviest among the Sensex Reliance Industries fell by Rs146.30, or 7.67%, at Rs1760.95. IT major Infosys fell by Rs62.95, or 4.33%, at Rs1390.95, ICICI Bank by Rs46.95, or 8.51% at Rs504.50, Tata Steel by Rs44.85, or 10.22% at Rs393.80 and Sterlite Industries by 7.84% at Rs395.75, its lowest in more than two years.

All the five carry nearly 40% weightage on the 30-scrip benchmark Sensex.