KARACHI- The Karachi Stock Exchange benchmark 100-share index plummeted over 400 points on today amid political instability. The index stood at 28416.71 points after it decreased by 1.51% till today afternoon. On Monday, the index fell 0.23% or 65.60 points, closing at 28,852.15 points. Uncertainty in the political situation has led to volatility in the market. Analysts reflected that if the current political scenario prevailed then the situation of stocks would also remain uncertain in future. The low volume showed the lack of interest on the part of investors as only an investment of Rs20 million took place. Today's decline comes as Imran Khan has announced that he would march into the Red Zone and Tahirul Qadri has called for the holding of a people's parliament in the federal capital.