Trading was halted for more than two hours on the New York Stock Exchange floor Wednesday after an internal technical issue was detected – which then set off speculation that a cyber-glitch at United Airlines and a temporary online outage at the Wall Street Journal newspaper were connected.

White House spokesman Josh Earnest said President Obama had been briefed on the glitch that took out trading on the floor of the NYSE by White House counterterrorism and homeland security adviser Lisa Monaco and chief of staff Denis McDonough.

He also said despite indications that it was not a cyber-breach, the administration was “keenly aware of the risk that exists in cyber space right now.”

Department of Homeland Security Secretary Jeh Johnson tried to allay fears, saying, “It appears from what we know at this stage that the malfunctions at United and at the stock exchange were not the result of any nefarious actor.”

He added, “We know less about the Wall Street Journal at this point except that their system is back up again as is the United Airline system.”

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Trading at the NYSE stopped around 11:30 a.m. ET though NYSE - listed shares continued to trade on other exchanges such as the Nasdaq.

The NYSE, which is owned by Intercontinental Exchange and is the world’s largest stock exchange based on market capitalization, has experienced technical difficulties in the past. However, Wednesday’s issue by all accounts was out of the ordinary.

Shortly after the outage, which was unusual and symbolic, the NYSE tweeted that the issue was internal and not a breach.

"The issue we are experiencing is an internal technical issue and is not the result of a cyber breach," the exchange tweeted. "We chose to suspend trading on NYSE to avoid problems arising from our technical issue."

Still, the timing of the event coincided with other cyber glitches.

The Wall Street Journal’s homepage displayed a 504 outage though other sections on the online paper’s website, continued to function. The homepage had been quickly restored following the outage.

“I think the Wall Street Journal piece is connected to people flooding their web site in response to the New York Exchange to find out what’s going on.” FBI Director James Comey told the Senate Intelligence committee. “In my business we don’t love coincidences, but it does appear that there is not a cyber-intrusion involved.”

Sen. Bill Nelson, D-Fla., the top Democrat on the cyber-security subcommittee, told Fox News that the NYSE incident has “the appearance” of a cyberattack and noted the coordination of multiple sites.

An FBI official told Fox News that the bureau has offered its assistance concerning the NYSE situation, but at this time it does not appear to be nefarious.

Stocks were already trading lower Wednesday when the glitch occurred. Traders had been worried about China’s inability to stop a steep drop in its own market. Traders have also been skittish as talks between Greece and its creditors seemed to have stalled.

U.S. stocks closed with sizable losses with the Dow Jones industrial average losing 261 points, Standard & Poor's 500 gave up 34 points and the Nasdaq was down 87 points.

Fox News’ Chad Pergram and Matthew Dean and the Associated Press contributed to this report.