I don't think they know if was was bots or an organized effort but the source is North Korea. It's being reported as a DDoS so probably bots. Seems like NK is getting more troublesome. I'm not pointing the finger at their gubment on this one just yet.
This is also more than a little concerning -
"The specter of cyberwarfare has led the Pentagon to develop a new cybersecurity command and raised questions about the government's ability to defend against attacks that could undermine national and financial security"
Article
This is also more than a little concerning -
"The specter of cyberwarfare has led the Pentagon to develop a new cybersecurity command and raised questions about the government's ability to defend against attacks that could undermine national and financial security"
Article