© Reuters/Brenden McDermid
"It's chaos. No one seems to know the root of the cause which seems to me is making everything worse," a source on the floor of the stock exchange said, according to Bloomberg reporter Leslie Picker.
The NYSE is reportedly rushing to fix the "technical problem," but there has been no official explanation why all floor trading has been halted. The exchange said it was canceling all open orders as well.
"We've had some technical malfunctions. Some may be related to connectivity with other exchanges. I believe we're going to have a temporary pause certainly in a variety of stocks perhaps floor wide," Art Cashin, director of floor operations at the NYSE, told CNBC.
The NYSE suspended all trading at 11:32, half an hour after initial reports of a technical problem, according to Yahoo Finance.
NASDAQ announced its systems were operating normally and trading NYSE securities.
Other exchanges, such as NYSE Arca and NYSE Amex/Arca Options, are "unaffected by this issue and continue normal operations at this time," the stock exchange said.
The Wall Street Journal website (wsj.com) was down as well.
Earlier today, United Airlines grounded its entire fleet for over three hours due to a computer problem.
Department of Homeland Security (DHS) officials said there was "no indication" of a cyber attack behind the problems at the NYSE, United Airlines or the Wall Street Journal's website.
The WSJ site was back online just after 12:00 p.m. ET.
Comment: Curiouser and curiouser! Are the PTB flexing their muscles here? How soon will Russia or China factor in or be blamed? How does Greece figure into this drama? Interesting times we live in. On with the show!