Users of popular microblogging service Twitter were unable to access the site for almost 30 minutes early Thursday.
A "general site outage" took Twitter down for 27 minutes from just after 3am GMT Thursday.
Visitors to the site were greeted with the "Fail Whale," an illustration of a whale used by Twitter to signify the site is over capacity, or a message advising a technical fault before access returned at 3:30am GMT.
"We’re now recovering from this unplanned downtime," Twitter said in a status message. "We apologize for the interruption in service."
The glitch pushed up Twitter's downtime this month to 41 minutes, according to Pingdom, a site that measures reliability of access to Web sites.
That's almost double the downtime recorded during March last year but still some way off August 2009, Twitter's worst month in the last year, when the site was down for a total of more than 6 hours.