A nationwide outage for CenturyLink customers, including those trying to reach 911 emergency service, dragged on for the better part of two days before its resolution late Friday.
It also affectedacross the country, prompting nationwide alerts to cellphones.
The Federal Communications Commission said Friday that it's launching an investigation into the disruptions.
As of about 6 p.m. PT on Friday, the problem seemed to have been resolved. CenturyLink said in a tweet that "all consumer services impacted by this event, including voice and 911, have been restored" and that any latency issues would be cleared within a few hours.
CenturyLink has not yet given any indication what caused the problems.
DownDetector reported initial signs of the outage around 1 a.m. PT Thursday.
"Our network is experiencing a disruption affecting customer services," CenturyLink tweeted Thursday morning. "We know how important services are to our customers and are working to restore services as quickly as possible."
A company representative confirmed that efforts continue.
As of Friday afternoon, the company said on Twitter that it's "made progress in restoring services across the network in the last several hours. We are focused on resolving remaining issues."
The FCC steps in
FCC Chairman Ajit Pai called the disruption of service "particularly troubling" in its "breadth and duration."
The effect on people's ability to reach 911 emergency services is "completely unacceptable," Pai said in a statement. He added that he has been in contact with CenturyLink to emphasize the urgency of restoring service and that he would be monitoring progress closely.
CenturyLink didn't immediately respond to a request for comment on the FCC's investigation.
Originally published Dec. 27 at 1:47 p.m. PT.
Updated Dec. 28 at 9:09 a.m. and 2:03 p.m. PT: Added company comment about progress toward restoring service and added FCC Chairman Ajit Pai's comment.
Updated Dec. 29 at 4:57 a.m. PT: Added CenturyLink's statement that service has been restored,
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