A document leaked by former National Security Agency contractor Edward Snowden states that the NSA has been sending agents into online games on Xbox Live and PC, in a bid to infiltrate online game communities. According to documents obtained by the Guardian, and published in full on ProPublica, the NSA has built mass-collection initiatives around the Xbox Live network, and extended these infiltration efforts to massively multiplayer online worlds like World of Warcraft and Second Life. In a document titled "Exploiting Terrorist Use of Games & Virtual Environments," the NSA believed that terrorists may be using these games as a communication network, and that leaving them under-monitored was a bad idea. Games can be used to talk anonymously, the document reads, and therefore allows potential terrorists to share information between each other, and essentially hide in plain sight. The Guardian's report says that it is currently unclear how the NSA accessed data from online games, or how many communications it collected together -- although it suggests that Linden Lab, the company behind Second Life, was helping the NSA out at some point. The report claims that the company had a meeting with the NSA in 2007, to explain how Second Life could be used "to understand the motivation, context and consequent behaviors of non-Americans through observation, without leaving U.S. soil." Notably, the Guardian stresses that the NSA document never gives evidence that terrorists are using video games to plot schemes and attacks. However, it claims that Xbox Live, Second Life and World of Warcraft accounts were found to be associated with the IP addresses and email addresses of Al-Qaida terrorists. Of course, this was not enough to be considered proof -- which is why the document suggests that online games need to be monitored. "Only then can we find evidence that Games and Virtual Environments are being used for operational uses," it reportedly reads. World of Warcraft studio Blizzard Entertainment said in a statement, "We are unaware of any surveillance taking place. If it was, it would have been done without our knowledge or permission." Both Microsoft and Second Life company Linden Lab declined to comment on the report. The entire document can be found on ProPublica.