Level 3 outage affects voice customers across United States #20161004001
UPDATE: Level 3 did post on Facebook at about 12:30pm EST that it had restored services:
On October 4, our voice network experienced service disruptions that affected some of our customers in North America. We know how important these services are to our customers. We were able to restore all services by 9:31 a.m. Mountain time. We are investigating the root cause of the outage.
This outage began between 10 & 11 am EST and has impacted landline, cellular, and voip communications of every communications company in the US.