The benchmark Sensex of Bombay Stock Exchange on Monday nosedived by nearly 264 points on selling pressure sparked by fresh political concerns after the DMK announced pulling out of the UPA government at the Centre.
Marketmen said weak global cues in the wake of soaring oil prices also dampened the sentiment.
The 30-share index, Sensex, closed with a loss of 263.78 points at 18,222.67, mainly due to shattered investor confidence in the aftermath of fresh political worries at New Delhi.
Meanwhile, continuing turmoil in Libya pushed the crude prices above 105 dollar at New York which spooked investors.
The Sensex has lost 11% this year, to become the worst performer in Asia.
In a similar fashion, the broad-based National Stock Exchange index Nifty dropped by 75.60 points to 5,463.15.
The auto sector suffered the most by losing 2.55% as Tata Motors dropped 3.64%.
The capital goods sector was the second worst performer at 2.36%.
The realty sector, an interest-sensitive sector, declined 1.66% and banking index 1.60%.
The small cap index lost 1.43% and the mid cap index 1.41%.