NYSE
The New York Stock Exchange. Reuters

UPDATE: 2:15 p.m. EDT

New York Stock Exchange president Thomas Farley told CNBC that trading will resume sometime around 2:45 p.m. EDT or 3:00 p.m.

UPDATE: 1:55 p.m. EDT

As the New York Stock Exchange (NYSE) trading stoppage continued into the afternoon, official Washington got involved. U.S. Securities and Exchange Commission chair Mary Jo White issued a statement saying the agency is "in contact with NYSE and are closely monitoring the situation and trading in NYSE-listed stocks. While NYSE is working to resolve the situation, NYSE and NYSE MKT stocks continue to trade normally through other trading venues."

The FBI and Department of Homeland Security are reportedly monitoring the halt and receiving updates from NYSE officials.

UPDATE: 12:55 p.m. EDT

Just before 12:30 p.m. EDT, the New York Stock Exchange said on Twitter that the source of the problem is "an internal technical issue and is not the result of a cyber breach."

Original story: The New York Stock Exchange (NYSE) unexpectedly halted all trading Wednesday morning just before noon EDT. The reason for the temporary suspension was attributed to technical issues. Trading on the Nasdaq, however, continued.

“We’re currently experiencing a technical issue we’re working to resolve as quickly as possible,” the stock exchange said in a brief statement. “Additional information will follow as soon as possible.”

NBC reporter Carl Quintanilla tweeted a photo from inside the exchange, showing one of the trading screens.

It was unclear if a cyber attack was to blame for the NYSE technical difficulties, according to the U.S. Department of Homeland Security.