Glenn Greenwald, the journalist who broke the Edward Snowden revelations, has come good on his promise that fresh information on the NSAs mass spying would be forthcoming. Today he reveals that the US government agency routinely intercepts computer hardware such as routers, switches and servers, and fits it with cutting edge surveillance equipment, before sending it back on its way.

In an article for The Guardian, Greenwald notes that the NSA tampers with the hardware, then repackages it with "factory sealing" before sending it off to unsuspecting companies who have no idea it has been intercepted.

Greenwald notes that the practice constitutes "an extreme form of gross hypocrisy," given that it has been warning companies around the world not to buy Chinese hardware because it may be set up with surveillance technology.

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