FBI and White House monitoring NYSE after "technical issue"

Trading on all shares was suspended on the New York Stock Exchange (NYSE) for technical reasons yesterday from 11:30am ET.

The exact cause of the problem effecting the world’s largest stock exchange is unclear, but the Wall Street Journal website also experienced issues.

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"We're currently experiencing a technical issue that we're working to resolve as quickly as possible," a spokeswoman for the NYSE said in a statement yesterday. "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."

Reuters is reported that all open orders will be cancelled and that the technical problem appears to be limited to the NYSE floor. The NYSE Arca and the NYSE Amex were not affected and the NASDAQ index was continuing to trade NYSE-listed stocks.

The New York Stock Exchange experienced an earlier computer issue prior to opening yesterday which had led to some concerns that a cyberattack could be the cause of the technical problems. An earlier glitch that grounded a United Airlines flights contributed to the speculation, but the two events appear to be unrelated.

Before the suspension, the NYSE was trading down due to a fall in Chinese markets and concern over the impact that this would have globally. It is not believed, however, that the technical fault will cause share prices to move.

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To add a further air of mystery, a tweet from the well-known hacking group Anonymous asked if tomorrow was likely to be a bad day for Wall Street.

It is known now that after a three and half hour half hour halt on trading, the issue seems to have been resolved and trading resumed around 3:10pm ET.

The White House Press Secretary Josh Earnest said that "There is no indication that there are mailicious actors involved" but added later that the White House is monitoring the situation. It is also known that the FBI is also monitoring the situation but issued a statement in which they said that "no further law enforcement action is needed at this time."