Equity indices plunged to over four-month lows on Monday as concerns over surging Omicron cases across the world jolted investors, sparking a heavy selloff in global markets. Relentless selling by foreign investors amid a hawkish tilt by central banks also weighed on sentiment, traders said. 

The 30-share BSE Sensex slumped 1,189.73 points or 2.90 per cent to end at 55,822.01—its lowest since August 23 this year. The NSE Nifty tanked 371 points or 2.18 per cent to end at 16,614.20. The market capitalisation of all BSE-listed companies tumbled by Rs 6.79 lakh crore. Experts said exploding Covid-19 cases, sustained selling by foreign institutional investors and slowing growth momentum in the developed economies have spooked markets the world over.