I think it was this one: http://www.theguardian.com/world/2013/jul/01/us-military-blo...
It is also completely true. As you might expect, .mil unclassified public networks are still strictly controlled and monitored, with all the invasive filters and MitM certificates you could ask for. I recall seeing mass-distribution e-mails "reminding" cleared personnel that they should not even be visiting WikiLeaks or Guardian.co.uk using their own equipment when they return home from work.
They actually expected people who saw classified material distributed from the web on their home computers to call and report it, so that the "spillage" experts could examine every bit of their privately owned hardware and permanently delete the classified material. It sounds ridiculous, but they were completely serious.
I cannot even imagine the sort of brain damage that would allow a person to have such an expectation.
This was a big issue when WikiLeaks started leaking info. There were regular memos circulated in DoD and DoE environments reminding people they weren't to be reading classified documents.