NETSCOUT has released a statement to BleepingComputer that the Facebook and Instagram outages were caused by a BGP routing error. "'At approximately 12:52PM EST on March 13th, 2019, it appears that an accidental BGP routing leak from a European ISP to a major transit ISP, which was then propagated onwards to some peers and/or downstreams of the transit ISP in question, resulted in perceptible disruption of access to some well-known Internet properties for a short interval. While not malicious in nature, such events can prove disruptive on a widespread basis. It is very important that all network operators implement BGP peering best current practices (BCPs), including prefix-lists, max-prefixes, 'peer-locking' via AS-PATH filters, RPKI Origin Validation (RFC6811), and other techniques incorporated into the industry Mutually Agreed Norms for Routing Security (MANRS) detailed at .' -Roland Dobbins, NETSCOUT Principal Engineer"