U.S. stock markets sold off sharply at the open, with major indexes losing 7%, triggering a trading half for 15 minutes. When they reopened, both the Dow Jones Industrial Average and S&P 500 were down slightly more than 7%.
Trading will be halted again if losses reach 13% at any time before 3:25 p.m. Eastern time.
U.S. Treasury yields moved slightly higher with the 10-year at 70 basis points in midmorning trading.
The stock market drop followed swooning European markets and deepening worries about the spread of the novel coronavirus, which the World Health Organization on Wednesday declared a pandemic. The European Central Bank announced measures to support bank lending and expanded its asset purchase program by 120 billion euros ($135.28 billion) but did not announce an interest rate cut.
There was a slew of other news before the U.S. market open, reacting to the pandemic. The National Basketball Association suspended its season, Tom Hanks and his wife reported from Australia they have been infected with the coronavirus and, most importantly, President Donald Trump addressed the nation with his response to the scourge.