CTL CenturyLink Inc

By Maria Armental 

Cuts to two fiber lines caused a widespread system failure at cable giant Comcast Corp. on Friday that knocked out cable, internet and phone services around the country.

It was unclear how many customers, business and residential, were affected nationwide, but Comcast said most service had been restored late Friday.

The Philadelphia company, one of the dominant telecom companies in the U.S. with more than 29 million business and residential customers, said the lines damaged are owned by CenturyLink Inc. and Zayo Group Holdings Inc.

A spokeswoman for CenturyLink issued a statement saying CenturyLink's network was working normally, though the company had "experienced two isolated fiber cuts in North Carolina affecting some customers that in and of itself did not cause the issues experienced by other providers." The spokeswoman didn't comment further.

A spokesman for Zayo said the company experienced a fiber cut in the New York area but all services had been since restored.

Fiber networks, which make up the backbone of the internet, transmit vast amounts of internet traffic, processing everything from online purchases to 911 calls.

Down Detector and Outage.Report, two websites that monitor the running of consumer-technology services, ranked the system failure as extreme and posted maps indicating large numbers of customers affected in the New York, Philadelphia and Washington, D.C., metro areas as well as San Francisco, Chicago and Denver. Reports of outages, according to the websites, spiked early Friday afternoon.

Some customers took to social media to discuss the outages, saying they were having trouble getting through the company's phones and online chats. Comcast, on Twitter, directed customers to an internal website that was at one point down as well, eliciting a second round of customer complaints.

Write to Maria Armental at maria.armental@wsj.com

(END) Dow Jones Newswires

June 29, 2018 20:37 ET (00:37 GMT)

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