gary cohnGary Cohn Chip Somodevilla/Getty Images
Stocks sold off Thursday as false rumors swirled that Gary Cohn, President Donald Trump's top economic adviser, was resigning. The concern on Wall Street was that Cohn's departure could stifle some of the administration's business-friendly plans including tax reform. 
The major equity indexes lost more ground after a van plowed into a crowd in Barcelona, Spain, in what authorities said was a terrorist attack. 
By the market close, the S&P 500 had logged its second largest one-day decline of the year. 
Safe haven trades like Treasurys and gold rallied as stocks sold off. The benchmark 10-year yield fell more than 3 basis points to 2.18%, and was hovering near its lowest level since the end of June. Meanwhile, gold climbed about $5 an ounce to near $1,288.
Here's the scoreboard: 
  • Dow: 21,750.73, -274.14, (-1.24%)
  • S&P 500: 2,430.01, -38.10, (-1.54%)
  • Nasdaq: 6,221.91, -123.19, (-1.94%)
  1. Walmart reported second-quarter earnings and revenue that topped Wall Street estimates, boosted by an increase in foot traffic and by strong online sales. Walmart said food categories delivered their strongest comparable-store sales performance in five years, as food inflation boosted performance by "approximately 30 basis points."
  2. Alibaba , China's top e-commerce firm, crushed analysts' estimates with a 56% rise in first-quarter revenue. The results were driven by growth in online sales, which make up most of its business.
  3. Activist investor Bill Ackman says shares of payroll-processor ADP could double in five years, and the company needs to improve its profit margins and integrate its business lines. Ackman's hedge fund Pershing Square disclosed earlier this month an 8% holding in ADP. Pershing Square's disclosure of its stake sparked a testy-back-and-forth between the activist fund and the company which handles many Americans' paychecks.
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