Nifty 50 index opened at 23,868.05 with a decline of -582.40 points or (-2.38 per cent), while the BSE Sensex opened at 77,056.75 with a decline of -1862.15 or -2.36 per cent, reflecting strong selling pressure across sectors. The sharp fall in domestic equities comes as crude oil prices surged approximately 25 per cent on Monday to USD 116 per barrel.