Speaking at an event held by news outlet Politico on November 10, Mr Jambon specifically named the PlayStation 4 as being "the most difficult communication" method for intelligence authorities to monitor in counter-terrorism efforts. PS4 is Sony's fastest-selling console ever. Credit:Bloomberg "It's very, very difficult for our [intelligence] services – not only our Belgian services but international services – to decrypt the communications via PlayStation 4," he said "WhatsApp is also a difficult one," he said, but noted intelligence services "could" decrypt the popular chat app. "PlayStation 4 should be very, very difficult; it's a challenge," he added.

Mr Jambon did not explain why the PlayStation Network was a challenge, but security analysts cite a range of factors. The PlayStation 4 gaming console. Mike Thompson, director of information security products and services at Linus Information Security Solutions, said because the PlayStation used a proprietary operating system with its own communication network and protocols – known as the PlayStation Network – it was harder to crack. "It uses a proprietary file system and the hard disk is also encrypted, making forensics (and hacking) very difficult," he said. The PlayStation Network runs on proprietary, encrypted technology.

"To monitor network communications effectively would therefore require specific PS4 tools to be crafted with access to the PlayStation Network and user accounts. This makes the PS4 a very difficult target to monitor." Director of information security firm Threat Intelligence, Ty Miller, added that it would be "inherently difficult" to gather intelligence from a gaming platform like PS4 because of the range of locations, identities and games that users could switch between to evade authorities. A scene from Call of Duty: Black Ops III. "You can change your alias at any point in time, you can change the location you're connecting from and the games you're actually chatting within, so it's going to be quite difficult to be able to track users across multiple aliases, games and locations," Mr Miller said. Games were also susceptible to "decoy attacks" whereby a platform is flooded with "fake" communications which distract from the "needle in the haystack" they are looking for, he said.

Another drawcard is that games can be used for steganography, whereby messages are hidden within normal forms of communication. For instance, terrorists could communicate within the framework of a game in a way that makes it difficult to tell whether they're talking about real-world events, or merely talking about the game. The often violent subject matter of many popular video games might provide a further cloak for such messages. "For example, maybe two terrorists are playing [war-time game] Call of Duty and talking about what they're going to shoot," said IT security expert Troy Hunt. Forbes writer Paul Tassi has noted the potential for terrorists to hide messages in non-verbal forms of communication within games, and it would be virtually impossible for authorities to know where to look for them. For instance, someone could spell out a message using coins in Super Mario Maker, which allows users to create their own levels for others to play. PlayStation has declined to comment on the matter.

Social media offensive During his discussion with Politico Mr Jambon said Belgian authorities were working with major technology companies including WhatsApp, Google and Facebook to remove online propaganda distributed by Islamic State through their channels. Authorities were also planning to distribute a "counter-narrative" via social media. Mr Jambon expressed fear at "lone wolves" being influenced by the "100,000 Twitter messages a day" distributed by IS. "What I'm afraid of is the guy who sits behind this computer, who is there searching the messages of IS and of the hate preachers, and then at a certain moment he is able to do violent actions and he comes out and he goes into a football stadium or a railway station ... "I don't think it can destabilise our society but it can provoke a lot of harm to our people and that is what I'm very much afraid of."