Mumbai: Key Indian equity market indices opened in the red on Friday following weak global markets on concerns over Brexit polls. The 30-scrip Sensitive Index (Sensex) was trading 35.66 points or 0.13 per cent down during the early session. The wider 51-scrip Nifty of the National Stock Exchange (NSE) was also trading 6.90 points or 0.08 per cent lower at 8,196.70 points. The BSE Sensex, which opened at 26,742.26 points, was trading at 26,727.80 points (at 9.16 a.m.) in the early session, lower 35.66 points or 0.13 per cent from the previous day's close at 26,763.46 points. The Sensex touched a high of 26,749.02 points and a low of 26,683.08 points in the trade so far.