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NEW YORK (AP) – An investigation by the U.S. federal telecom regulator says about 12,600 callers couldn’t reach 911 directly from their cellphones during a five-hour AT&T outage on March 8.

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A Federal Communications Commission official said Thursday that the outage affected AT&T customers in the Southeast, central U.S. and parts of the Northeast as well as a significant number of callers in other parts of the country.

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Lisa Fowlkes, the head of the agency’s public safety unit, says an AT&T network change caused the problem. A backup call center that attempted to manually connect calls couldn’t handle the volume.

Fowlkes also says a second AT&T wireless phone call outage occurred March 11 but only a small percentage of 911 calls were affected. She says AT&T says the two problems were unrelated.

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