Bharat Petroleum and Indian Oil were the top percentage laggards on the 50-scrip index in afternoon

Oil refinery stocks plunged on Monday, after an attack on Saudi Arabian oil facilities shut about 5 per cent of global supply, leading to the biggest percentage surge in crude oil prices since 1991. Shares in state-run oil companies Bharat Petroleum, Hindustan Petroleum and Indian Oil fell as much as 6.97 per cent, 7.31 per cent and 4.08 per cent respectively in the first half of the day. Shares in private sector energy conglomerate Reliance Industries dropped as much as 3.02 per cent to Rs 1,188.50 apiece on the Bombay Stock Exchange (BSE), and were among the top three drags on the benchmark Sensex index. (Also read: Crude oil price clocks biggest percentage gain since 1991)

Brent crude futures - the international benchmark for crude oil - rose by as much as 19.5 per cent to $71.95 per barrel on Monday, marking its biggest intraday percentage jump since January 14, 1991.

Bharat Petroleum and Indian Oil were the top percentage laggards on the 50-scrip benchmark index Nifty in afternoon.

The Nifty Energy index - comprising shares of petroleum, gas and power companies - fell as much as 2.02 per cent during the session. Besides BPCL, HPCL, IOC and Reliance Industries, the index includes six other stocks including NTPC, Tata Power and Power Grid - which declined 1.33 per cent, 1.71 per cent and 0.81 per cent respectively.

The S&P BSE Energy and Oil & Gas sectoral indices fell 2.55 per cent and 2.02 per cent respectively.

At 12:47 pm, Hindustan Petroleum, Bharat Petroleum, Indian Oil and Reliance Industries stocks traded with losses of 7.06 per cent, 6.52 per cent, 2.46 per cent and 1.20 per cent respectively, underperforming the benchmark Nifty index which was down 0.61 per cent.