Blogger.com was offline for an hour early Wednesday as Google’s popular service encountered performance problems. Blogger is one of the oldest and largest blogging services, hosting several million free blogs. Google “apologized profusely” for the service interruption.

“Blogger and Blog*Spot had an unexpected outage for an hour this morning, starting around 7AM PDT,” Google reported on its Blogger status page. “As of 8AM, all but a few blogs are working properly again.” The company didn’t offer any additional details on the cause of the outage. The Google search engine and other services were unaffected, as the outage appears to have been isolated to Blogger and blogspot.com.