Problems accessing your Twitter account yesterday? You’re not alone. The microblogging site experienced a large crash on Tuesday morning which affected most of its 645 million users.

On Tuesday morning, Twitter experienced a loss of service for around 45 on both its web page and mobile apps. According to the company’s official blog, the down time affected “most users”, but was fully restored to everyone within an hour of the initial shut down. There is no concrete explanation yet for what caused the loss of power, though it is currently being investigated by Twitter.

Although the down time was not expected, it happened during scheduled servicing activity and received quick action from Twitter’s technicians. The official statement from the social media site on their loss of service was issued on a company blog.

“During a planned deploy in one of our core services, we experienced unexpected complications that made Twitter unavailable for many users starting at 11:01am. We rolled back the change as soon as we identified the issue and began a controlled recovery to ensure stability of other parts of the service.”