The company stated on its Twitter Status Blog that "Users may be experiencing issues accessing Twitter. Our engineers are currently working to resolve the issue."
After three hours, the company updated their blog, stating that the issue had been resolved.
Later in the afternoon, Mazen Rawashdeh, Twitter's vice president of engineering, posted on the company blog that the outage was due to system failures in their data centers. The failure was unusual though because when one system fails, another parallel system is designed to take over, but two systems failed at the same time, so there was no back-up system to kick in.
"I wish I could say that today’s outage could be explained by the Olympics or even a cascading bug. Instead, it was due to this infrastructural double-whammy. We are investing aggressively in our systems to avoid this situation in the future," Rawashdeh said.
Twitter experienced an outage last month caused by a "cascaded bug" in the company's systems that kept users from accessing the network.
Google's chat service, Google Talk, also experienced an outageThursday morning that lasted several hours.
Twitter did not immediately respond to a request for comment.