The New York Stock Exchange halted trading on all shares on Wednesday afternoon at 11:30 a.m. due to a "technical issue," and said that all open orders will be canceled.
The New York Stock Exchange tweeted the reason for the trading halt was due to a technical issue, not a cyber attack.
Nasdaq declared "self help" against the exchange, meaning it will route trades away from the NYSE and to other exchanges like the Nasdaq and BATS. Meanwhile, NYSE said its all-electronic ARCA and options markets remain open, and unaffected by the issue.
"We're currently experiencing a technical issue that we're working to resolve as quickly as possible. We will be providing further updates as soon as we can, and are doing our utmost to produce a swift resolution, communicate thoroughly and transparently, and ensure a timely and orderly market re-open," a NYSE spokesperson said via email.
Securities and Exchange Commission Chair Mary Jo White said is keeping close tabs on the developments at the NYSE.
"We are in contact with the NYSE and are closely monitoring the situation and trading in NYSE-listed stocks," she said in a statement. "While NYSE is working to resolve the situation, NYSE and NYSE MKT stocks continue to trade normally through other trading venues.
A Nasdaq spokesperson said the exchange's systems were "operating normally and are trading all symbols including Tape A (NYSE) securities."