The issue focused mostly on how the US government would handle the fallout of the hack.

"The Department of Defense is committed to protecting classified information and conducting sensitive research, but there's no guarantee that the information you're sharing with us will be protected. In fact, the information you share could be used against you," a statement from the Department of Homeland Security said.

The statement also said "we're working closely with our partners, industry partners, and others to ensure that sensitive information is protected."