Equity benchmark indices Sensex and Nifty tanked over 2 per cent each on Thursday, dragged by a decline in heavyweight stocks Reliance Industries, HDFC Bank and spiralling conflict in the Middle East.

Falling for the fourth day running, the BSE Sensex tumbled 1,769.19 points or 2.10 per cent to settle at 82,497.10. During the day, it plummeted 1,832.27 points or 2.17 per cent to 82,434.02.

The NSE Nifty slumped 546.80 points or 2.12 per cent to 25,250.10.

Continuous foreign fund outflows and rising crude oil prices dented investors' sentiment, analysts said.

From the 30 Sensex firms, Larsen & Toubro, Reliance Industries, Axis Bank, Asian Paints, Tata Motors, Bajaj Finance, Maruti, Bajaj Finserv, Kotak Mahindra Bank, Titan, Adani Ports and HDFC Bank were the major laggards.

JSW Steel emerged as the only gainer.

"The domestic market took a sharp downturn following Iran’s launch of ballistic missiles at Israel, sparking fears of retaliation and escalation in war,” Vinod Nair, Head of Research, Geojit Financial Services said.

“New SEBI regulations for the F&O segment have raised concerns about reduced trading volumes in the broader market. Lastly, with attractive valuations in China, FIIs have redirected their funds, adding pressure on Indian stocks," Nair added.

In Asian markets, Hong Kong settled lower while Tokyo ended in the positive territory. Markets in mainland China will be closed for the rest of the week due to holiday.

European markets were trading mostly lower. The US markets ended marginally higher on Wednesday.

Foreign Institutional Investors (FIIs) offloaded equities worth Rs 5,579.35 crore on Tuesday, according to exchange data.

Global oil benchmark Brent crude climbed 1.37 per cent to USD 74.91 a barrel.

Equity markets were closed on Wednesday for Mahatma Gandhi Jayanti.

The BSE benchmark dipped 33.49 points or 0.04 per cent to settle at 84,266.29 on Tuesday. The Nifty ended marginally lower by 13.95 points or 0.05 per cent to 25,796.90.