CNBC said customers from NY to California reported outages.
"Restoring impacted services for our customers is very important to us".
CenturyLink calls itself "the second largest USA communications provider to global enterprise customers". A media representative was not available for comment. But the company says it does not yet know the extent of service outages.
Ajit Pai, chairman of the Federal Communications Commission, ordered on Friday an investigation into the outage.
Beyond the company's tweets, CenturyLink has not issued any official statements on the outage.
Regulators in Washington state also said they were opening an investigation into an outage of its statewide 911 service. ISP CenturyLink's network recently went down in certain parts of the USA (including Washington, Idaho, and Missouri) knocking out each location's 911 services in the process. KOMO reports that some CenturyLink customers reported receiving busy signals when dialing 911.
The problem caused business disruptions in eastern Idaho and 911 emergency services were reportedly affected in other parts of America.
Some ATM machines weren't working in Idaho and Montana. Patient records have been hard to access for medical centres in north Colorado and for other locations that haven't been confirmed. "The CenturyLink service outage is therefore completely unacceptable, and its breadth and duration are particularly troubling".
"Where CenturyLink is the 911 service provider 911 calls are completing", the company said in a tweet. CRESA said it pushed information about reaching 911 through "all other methods" before sending a message through its Emergency Alert System and Wireless Emergency Alerts systems Thursday evening.
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