If you've been having problems with your T-Mobile USA phone today, don't worry, you didn't forget to pay your bill. Well, maybe you did, but that's not the issue. The Bellevue-based company tonight acknowledged that it has been hit by an outage, without specifying the cause.

“Some T-Mobile customers may be experiencing intermittent service disruptions impacting voice and some data services," the company said in a statement issued this evening. "Our rapid response teams have been mobilized to restore service as quickly as possible. We will provide updates as more information is available.”

We first encountered the problem this afternoon when trying to call a family member with a T-Mobile account. First the system informed us that the number we were calling was no longer valid. Subsequent attempts to call the same number returned a busy signal. Later this evening, however, it started working again.

In terms of customer service, this isn't exactly what T-Mobile needs right now, after all the problems caused by Microsoft subsidiary Danger for T-Mobile Sidekick users. We'll update this post as the company issues more information. In the meantime, if you're a T-Mobile customer, let us know your status in the comments below.

Update, 6:30 p.m.: Here's the latest statement from the company: "We’re making good progress restoring voice and messaging service to affected customers. At this time, approximately 5 percent of T-Mobile customers are experiencing service disruptions. Issues began at approximately 5:30 p.m. Eastern time. Our rapid response team is working continuously to fully resolve this disruption. We sincerely apologize for the inconvenience that this has caused our customers."

Update, 11:20 p.m.: T-Mobile says service is back. Here's the statement: "T-Mobile confirms it has fully restored voice and text/picture messaging services for customers affected by intermittent service disruptions on Tuesday. About five percent of our customers across various geographies were affected for much of Tuesday evening, and by late Tuesday PST their service was restored. Our sole focus has been restoring full services for all customers; we are now investigating the root cause of the incident. We sincerely apologize for the inconvenience that this has caused our customers."

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