Mumbai: Indian equity markets on Wednesday succumbed to profit booking on uncertainities regarding the passage of the GST (Goods and Services Tax) Bill in the Rajya Sabha. Consequently, both the key indices provisionally closed the day's trade in the negative territory, as heavy selling pressure was witnessed in automobile, capital goods and consumer durables stocks. The wider 51-scrip Nifty of the National Stock Exchange (NSE) edged down 83 points or 0.96 per cent to 8,539.90 points. The barometer 30-scrip sensitive index (Sensex) of the BSE, which opened at 28,008.52 points, provisionally closed at 27,697.51 points (at 3.30 p.m.) -- down 284.20 points or 1.02 per cent from the previous close at 27,981.71 points. The Sensex had touched a high of 28,015.43 points and a low of 27,690.06 points during the intra-day trade. The BSE market breadth was skewed in favour of the bears -- with 1,815 declines and 914 advances. Both the indices had ended marginally in the red during the previous trade session on Tuesday, prompted by negative global cues and profit booking. The barometer index fell by 21.41 points or 0.08 per cent to 27,981.71 points, while the NSE Nifty edged lower by 13.65 points or 0.16 per cent to 8,622.90 points.