SEATTLE (AP) - T-Mobile subscribers are having problems sending text messages and receiving phone calls.

It's not known how widespread the service outage is or what caused it.

T-Mobile representatives did not immediately return calls seeking more information.

However, calls placed to the cellphones of several T-Mobile representatives could not be connected.

T-Mobile's official Twitter account says the company is aware of the disruption and has sent teams out to fix it.

This could be the second black eye for T-Mobile, a unit of Deutsche Telekom AG, in less than a month.

In October, a server failure caused customers with Sidekick-brand phones to lose much of their data.

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