AT&T Says The Outage To Its U.S. Cellphone Network Was Not Caused By A Cyberattack

AT&T said the hourslong outage to its U.S. cellphone network Thursday appeared to be the result of a technical error, not a malicious attack.

The outage knocked out cellphone service for thousands of its users across the U.S. starting early Thursday before it was restored.

AT&T blamed the incident on an error in coding, without elaborating.

“Based on our initial review, we believe that today’s outage was caused by the application and execution of an incorrect process used as we were expanding our network, not a cyber attack,” the Dallas-based company said.

Outage tracker Downdetector noted that outages, which began at about 3:30 a.m. ET, peaked at around 73,000 reported incidents. AT&T had more than 58,000 outages around noon ET, in locations including Houston, Atlanta and Chicago. The carrier is the country’s largest, with more than 240 million subscribers.

By 9 p.m. ET, the reports on AT&T’s network were fewer than 1,000.

Cricket Wireless, which is owned by AT&T, had more than 9,000 outages at one point but the reports had also tailed off later in the afternoon. Users of other carriers, including Verizon and T-Mobile, also reported issues but those companies said their networks were operating normally and the problems were likely stemming from customers trying to connect to AT&T users.

During the outage, some iPhone users saw SOS messages displayed in the status bar on their cellphones. The message indicates that the device is having trouble connecting to their cellular provider’s network, but it can make emergency calls through other carrier networks, according to Apple Support.

The Federal Communications Commission contacted AT&T about the outage and the Department of Homeland Security and FBI were also looking