Hackers claim to have found sensitive Nato documents contained in a massive email haul stolen from British tabloid The Sun.
Leaders of the Anonymous activist movement are crawling through 4Gb of emails stolen from the newspaper, and say the phone hacking scandal embroiling News International, publisher of The Sun "isn't s---" compared to what has already been uncovered.
The activists claimed to hold 1Gb of Nato documents and said some were so sensitive that they would be withheld from publication.
"We are sitting on about one gigabyte of data from Nato now, most of which we cannot publish as it would be irresponsible. But oh Nato," said Sabu, a leader in the group, in a tweet.
Sabu said that the group "may not" release The Sun emails "simply because it may compromise the court case", but later began working with some unnamed media outlets on the content.
Investigations by the group into the emails had not yet uncovered information that may explain how The Sun came to acquire the alleged sensitive Nato documents.
The Sun did not immediately respond to questions on the matter.
The group released an alleged Nato document from the emails stamped "restricted" and dated January 2008. It stated Nato had outsourced its Communications and Information Systems support deployed in the Balkans.
SC understands the emails contain email exchanges dated from this year to at least early 2009 prior to the marriage of former News International executive Rebekah Brooks.
This publication also understands the emails were stolen from a hacked MX server used to handle email.
Along with attachments, Anonymous is searching through news articles and office exchanges within the emails.
It will also release stolen data on a royal family, information on SCADA systems used to control big utilities, for instance, four federal contractors and two "foreign" banks among others.
That data was stolen in separate hacks, SC Magazine believed.
The claims by the activists cannot be verified, however Sabu together with others in the groups have previously released batteries of stolen data from companies including Fox, the CIA and Monsanto.
This week, the reformed LulzSec group claimed credit for attacking the homepage of The Sun.
It said in a tweet that The Sun hack was just the start, and that "the real damage is currently giving the admins heart attacks".
In that attack, it allegedly injected a redirect into an iFrame that pointed visitors to a fake news article which claimed owner Rupert Murdoch was found dead. It exploited vulnerabilities on a disused News International Solaris server.
The LulzSec and Anonymous groups have historically posted stolen data to BitTorrent website The Pirate Bay.
Such actions have drawn the ire of PayPal chief security officer Michael Barrett who called on organisations to identify those involved.