Equity benchmark Sensex on Monday crashed over 491 points, piling on losses for the fourth session in a row, amid investors fearing that Indo-US import tariff tussle might open a new front in the global trade war. Also Read - Fact Check: Students to Be Rewarded With Rs 1 Lakh Scholarship Through National Scholarship Exam? Here's The Truth

Likewise, the NSE gauge slipped over 151 points to close below the 11,700-mark. Also Read - Stock Market Crash: Sensex Nosedives 1,115 Pts, Nifty Tanks Below 10,850-mark in Closing Session

Besides, fresh geopolitical tensions in the Middle East and concerns over the advancement of monsoon also unnerved market participants. Also Read - Happiest Minds Technologies Makes Bumper Market Debut, Lists At 111% Premium Over Issue Price

The BSE gauge settled 491.28 points, or 1.25 per cent, lower at 38,960.79. The index hit an intra-day low of 38,911.49 and a high of 39,540.42.

Similarly, the broader NSE Nifty cracked 151.15 points, or 1.28 per cent, to close at 11,672.15. During the day, the index touched a low of 11,657.75 and a high of 11,844.05.

Over the past four sessions, the Sensex has lost 796.02 points or 2 per cent.

Sectorally, BSE metal was the worst hit, losing over 3 per cent, while energy index fell over 2 per cent on Monday.

Broader BSE midcap and smallcap indices followed benchmarks, dropping up to 1.35 per cent.

On the Sensex, Tata Steel emerged as the biggest loser with over 5 per cent fall. Other major laggards were Vedanta, Tata Motors, Axis Bank, Bharti Airtel, Reliance, ONGC, Sun Pharma, Maruti and L&T, falling as much as 3.33 per cent.

Bucking the weak market trend, Yes Bank, Coal India and Infosys rose.

India has effected a hike in customs duties on as many as 28 US products, including almond, pulses and walnut, in response to higher tariffs imposed by Washington on Indian products like steel and aluminium.

“Domestic market has been caught in a bearish grip as investors are increasingly turning cautious led by global trade war which has got murkier. Additionally, geopolitical tensions in the Middle East triggered a sudden spurt in oil prices. Domestic market consolidation will be maintained till global events unfold like central bank and GST council meet this week,” said Vinod Nair, Head of Research, Geojit Financial Services.

On the currency front, the Indian rupee depreciated by 10 paise to close at 69.91 against the US dollar Monday.

Global oil benchmark, Brent crude futures fell 0.46 per cent lower at USD 61.76 per barrel.

Asian markets Monday showed a mixed trading pattern, with Seoul stocks ended in the red, while bourses in Shanghai, Hong Kong and Tokyo closed higher.

Exchanges in Europe were also trading in the green in early deals.