The stock market reacted sharply to Finance Minister P Chidambaram's Budget for 2007-08, as the benchmark Sensex tanked over 529 points to again slip below the 13,000 level.
The wide-based NSE index Nifty plunged by 132 points at 3,762.05.
Even before Chidambaram finished announcing tax proposals, the market went into a free-fall reflecting investors disappointment at industry, particularly auto, not being given any relief.
All Sensex-related auto stocks, including Bajaj Auto, Hero Honda, Maruti Udyog and Tata Motors, were trading down.
The auto index was down about three per cent at 5,152 points.