When Apple introduced iCloud activation lock the thefts on iPhones went down, however, a new scam rose which was to sell devices and iCloud lock them.
Unfortunately there is currently no way around this and if you are a victim of this we recommend you report them to the police, the good news is there is a way to restore some functionality to the device so you are not left with just a brick.
When you go to setup your device you are greeted with an activation lock screen you need to select option and start over then go to the section where you choose your wifi options.
22.214.171.124 or 126.96.36.199
188.8.131.52 or 184.108.40.206
Then go back and continue to connect to your wifi.
You will then be presented with the server you typed in and you can access certain features such as social networking apps, messaging apps and even email.
Congratulations you now have a device that is not 100% useless.