Stock market live updates: Worst start in 5 years, Dow drops 380, new lockdown for England

This is a markets live blog for CNBC PRO subscribers that will be updated throughout the day.

The major averages gave up opening gains quickly and traded deep in the red on Monday. At one point, the Dow was off by more than 700 points. Stocks were coming off a surprisingly strong year that saw the S&P 500 and the Dow close at record highs on the last day of 2020.