All trading on the NASDAQ market was halted on Thursday due to a glitch in a system used to disseminate trading information.
First signs of a problem were seen at 10:57 EDT (14:57 GMT) when "momentary interruptions in quote dissemination" hit a system that pools data from exchanges that trade NASDAQ securities. Those problems lasted for six minutes before the system returned to normal operation, according to a market status message issued by the exchange.
But roughly an hour later, NASDAQ said there were problems with submission of quotes to the same system. As a result, NASDAQ halted trading at 12:14 EDT and the options market followed suit at 12:20 EDT.
No further details are currently available.
NASDAQ operates one of the two top stock exchanges in the U.S. It is particularly popular with tech companies.
Martyn Williams covers mobile telecoms, Silicon Valley and general technology breaking news for The IDG News Service. Follow Martyn on Twitter at @martyn_williams. Martyn's e-mail address is firstname.lastname@example.org