Sensex fell over 323 points after an intense sell-off during the closing hours on Wednesday triggered by losses mainly in index heavyweights Infosys, Reliance and HDFC. After spending most part of the day in green, the BSE close 0.55 per cent or 323.34 points to close at 58,340.99 - reversing the gains acquired on Monday after a four-day losing streak. Tuesday's performance marked its fifth day of decline in the last six days. Likewise, the NSE Nifty fell 88.30 points or 0.5 per cent to close at 17,415.05.