The BSE benchmark Sensex fell nearly 300 points to crack below the 34,000-mark on Monday amid weak Asian cues after a US-led strike on Syrian targets fuelled fresh geopolitical concerns.
The 30-share index fell by 293.31 points, or 0.85 per cent, to 33,899.34 in opening trade.
The gauge had gained 1,173.88 points in the previous seven sessions.
BSE sectoral indices, led by IT, Teck, oil and gas, PSU, power, infrastructure and banking stocks, declined up to 1.45 per cent.
The NSE Nifty was trading lower by 84.25 points, or 0.80 per cent, at 10,396.35.
Shares of Infosys fell 3.86 per cent to Rs 1,123.90 less-than-expected FY19 revenue guidance. The stock was the biggest contributor to the losses on Sensex.
Other major losers were Tata Motors, Wipro, Axis Bank, ONGC, NTPC, RIL, Dr Reddy's SBI, Bharti Airtel, ICICI Bank, Maruti Suzuki, Asian Paint and Tata Steel, falling by up to 1.54 per cent.
Among other Asian markets, Hong Kong's Hang Seng shed 1.44 per cent, while Shanghai Composite Index was down 1.05 per cent in early trade. Japan's Nikkei, however, was up 0.26 per cent.
The US Dow Jones Industrial Average ended 0.50 per cent lower in Friday's trade.