Following the drop, ONGC and RIL witnessed a combined erosion of Rs 18,177 crore in market valuation today.
Shares of ONGC fell by 3.21 per cent to Rs 349.35, becoming the top loser among the 30 Sensex components.
The market capitalisation of ONGC fell by Rs 9,923.95 crore to Rs 2,98,886.05 crore.
RIL lost 2.76 per cent, while GAIL was down by 2.50 per cent, Cairn by 2.30 per cent and Petronet LNG by 1.31 per cent on the BSE.
The BSE oil and gas index settled 2.48 per cent lower at 10,065.08.
"Shares of ONGC opened lower and continued to slip on account of falling crude prices. Profit taking was seen after rise of 2.5 per cent in yesterday's session," said Kiran Kumar Kavikondala, Director & CEO, WealthRays Securities.
Brent crude oil fell to five-year low below USD 65 a barrel, putting pressure on oil companies.
