Mumbai, Oct 3: Benchmark BSE Sensex tanked 1,769 points to slide to a three-week low on Thursday as a spiralling conflict in West Asia triggered selling in oil, banking and auto shares, wiping out Rs 9.78 lakh crore investor money in a single day.

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, its lowest closing level since September 11. During the day, it plummeted 1,832.27 points or 2.17 per cent to 82,434.02. As many as 29 Sensex scrips closed in the red while only one stock ended in the green.

Market capitalisation of BSE-listed companies dropped by around Rs 9.78 lakh crore to Rs 4,65,07,685.08 crore (USD 5.54 trillion).

The NSE Nifty slumped 546.80 points or 2.12 per cent to 25,250.10 with 48 of its constituents ending lower.

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 the 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.

The BSE midcap gauge tumbled 2.27 per cent and smallcap index dropped 1.84 per cent.

All indices ended lower. Realty tanked 4.49 per cent, while capital goods (3.18 per cent), auto (2.94 per cent), services (2.87 per cent), industrials (2.75 per cent) and oil & gas (2.52 per cent) were among the major losers.

A total of 2,881 stocks declined while 1,107 advanced and 88 remained unchanged on the BSE.

"Fears of FPIs and FIIs switching to China from Indian equities were prevalent, especially considering the sharp valuations of domestic markets compared to China," said Devarsh Vakil, Deputy Head of Retail Research, HDFC Securities.

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 the 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.