The Sensex was down by 13.89 points or 0.04 per cent at the Wednesday's closing.
The BSE and NSE will remain closed on Monday on the occasion of Id Ul Fitr.
The 30-share Sensex rose over 75 points in morning trade and shot up to 31,365.39, but quickly lost momentum to hit the day's low of 31,110.39.
Minutes into trading, it was quoting at 31,370.11 points, up by 86.47 points, or 0.28 per cent. Market was extremely volatile in the week with Sensex hitting record high and breaching 31,500 on Thursday. It had gained 7.10 points in the previous session.Similarly, the broader 50-share NSE Nifty moved up 17.65 points, or 0.18 per cent, at 9,647.65.More news: Doctor says Otto Warmbier has brain damage
Domestic institutional investors (DIIs) also bought shares worth a net Rs 455.21 crore.
The Nifty PSU Bank index dropped as much as 1.2 percent.
The Nifty Auto index fell as much as 1.3 percent. Market breadth was in the favour of losers, with about 3 stocks falling to every 1 stock that advanced.
The Indian equity markets traded in the red during the mid-afternoon session on Friday as broadly negative global cues, coupled with caution ahead of the Goods and Services Tax (GST) implementation and heavy selling pressure in automobile, capital goods, oil and gas and banking stocks subdued investor sentiments.