NEW YORK, Jan. 24 (Xinhua) -- Trading in dozens of names on the New York Stock Exchange (NYSE) was briefly halted shortly after the U.S. stocks markets opened on Tuesday.
The major stocks impacted included Morgan Stanley, Verizon, AT&T, Nike, Walmart and McDonald's, according to the NYSE's website.
The affected companies resumed trading shortly thereafter, according to a status report from the NYSE at around 9:50 a.m. ET, which said "all systems are currently operational."
An update on the stock exchange's website said the issues with the opening auction were being investigated.
"In a subset of symbols, opening auctions did not occur. The exchange is working to clarify the list of symbols," said the exchange.
The NYSE, like some other exchanges, issue automatic halts for stocks that move dramatically up and down. On a normal trading day, few if any stocks are halted for volatility on the NYSE.
U.S. stocks traded slightly lower at midday on Tuesday.
The Dow Jones Industrial Average slipped 21.17 points, or 0.06 percent, to 33,608.396. The S&P 500 lost 7.58 points, or 0.19 percent, to 4,012.23. The Nasdaq Composite Index decreased 17.72 points, or 0.16 percent, to 11,346.69.