The feds have been investigating Silk Road — a major web site on the secret internet for criminals — and the Tor web network and browser you need to visit it, for years. The probe goes back to January 2011.

Here's how it went down:

Tor first popped onto the national security/federal crime radar, at least publicly, in June 2013, when a photo emerged of NSA leaker Edward Snowden's laptop, which features a Tor sticker.

Because Tor allows secret, anonymous and encrypted web browsing, it would be the perfect vehicle for someone like Snowden to store or transport secrets.