S&P 500 slides as revived lockdown fears offset stimulus progress

• The S&P 500 declined on Monday as a mutated COVID-19 virus strain found in the UK dented reopening optimism and offset the $900 billion stimulus deal struck by Congress.
• The Dow Jones industrial average finished in positive territory after tumbling as much as 424 points.
• The mutated virus strain is said to be more contagious and has led to new lockdown measures and travel restrictions in the UK just ahead of Christmas.
• Congress agreed to pass another round of stimulus that will include $600 stimulus checks and extended unemployment benefits.
• Watch major indexes update live here.

The S&P 500 declined on Monday as investors grappled with a new COVID-19 strain identified in the UK that's said to be more contagious. The Dow Jones industrial average finished in positive territory after tumbling as much as 424 points at intraday lows.

Renewed virus concerns outweighed the $900 billion stimulus deal from Congress that includes $600 stimulus checks and expanded unemployment benefits.

Much is still unknown about the mutated virus, including how well vaccines from Pfizer and Moderna can protect against it.

Surging COVID-19 cases and concerns about the new variant of the virus have led to lockdown measures and travel restrictions for the UK. France, Germany, Italy, Ireland, and the Netherlands have banned flights from the UK, and Austria and Sweden are preparing to do the same.

Here's where US indexes stood at the 4 p.m. ET market close on Monday:

• S&P 500: 3,694.92, down 0.4%
• Dow Jones industrial average: 30,216.45, up 0.1% (37 points)
• Nasdaq composite: 12,742.52, down 0.1%

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Travel stocks plummeted on Monday as investors grappled with the renewed risk of a longer shutdown and travel restrictions. Tesla tumbled as it was officially entered into the S&P 500 index. Meanwhile, a $4.4 billion takeover of Aerojet Rocketdyne by Lockheed Martin helped spur a 26% surge in the rocket manufacturer.

Bitcoin suffered a steep drop from record highs on Monday as crypto investors grappled with a hack of the personal wallet system Ledger and new proposed rules from the US Treasury that would require exchanges to collect identifying information for its users who transfer more than $10,000 to a crypto wallet.

Oil prices edged lower. West Texas Intermediate crude dropped as much as 6%, to $46.18 per barrel. Brent crude, oil's international benchmark, declined 5.9%, to $49.20 per barrel, at intraday lows.

Gold fell as much as 1.4%, to $1,855.41 per ounce.

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