Tens of thousands of Americans awoke Thursday morning to discover their cell phones were bereft of signal. In addition to being unable to touch base with friends, families, and coworkers, some users apparently were unable to hail 911.

While those affected by the cascading cellular service outages appear to be predominantly AT&T customers, clients of other service providers are reportedly experiencing issues.

Around 3 a.m., there was a spike in reports of AT&T outages on the website Downdetector. As of 9:02 a.m. ET, there were over 73,000 reporters of customers experiencing service issues.

While Verizon, T-Mobile and other providers similarly saw spikes, Downdetector indicated they were orders of magnitude smaller. Verizon and T-Mobile maintain that their networks were unaffected and operating normally.

A spokesman for T-Mobile told CBS News, "Downdetector is likely reflecting challenges our customers were having attempting to connect to users on other networks."

"Some customers experienced issues this morning when calling or texting with customers served by another carrier," Verizon said in a statement obtained by the New York Times. "We are continuing to monitor the situation."

While AT&T has confirmed that it is experiencing rampant outages, it failed to provide an explanation for why the failure occurred in the first place, reported CNN.

"Some of our customers are experiencing wireless service interruptions this morning. We are working urgently to restore service to them," the company said in a statement. "We encourage the use of Wi-Fi calling until service is restored."

A spokesman for the company indicated further that AT&T's first responder network nevertheless remains operational.

The outages prompted some speculation online about possibly wicked causes, such as an electromagnetic pulse strike or a cyberattack; however, an industry source who spoke to CNN under the condition of anonymity suggested the issue is likely linked to a process known as peering, whereby cellphone services pass off calls from one network to the next.

CNN noted that the company was experiencing sporadic outages earlier this week, including a drop in 911 service in various southeastern states.

Blaze News reached out to AT&T for comment on the extent and cause of the outages as well as a projected timeline on a remedy but did not immediately receive a reply.

Various municipalities and local authorities across the country have confirmed the outages, in some cases highlighting corresponding difficulties reaching first responders by phone.

The City of Upper Arlington in Ohio noted that outages were affecting fire alarms, such that first responders "may not be notified of an activation." The city advised residents to follow up alarms with a 911 call "for the foreseeable future."

The San Francisco Fire Department noted that while the San Francisco 911 center was still operational, 911 calls had reportedly been impacted for some customers.

Various other official channels, including the X accounts for the City of Little Rock, Arkansas, the Rockville City Police Department of Maryland, and Orlando Police Department in Florida noted similar difficulties. A common recommendation: Use family or friends as proxies for 911 calls or call from a landline.

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