BCEmporium: How can you say what you would do when you don't know what is really happening? If I allow him to trade and he is a scammer it is very easy to send the majority of his money to another account just by clearing out the order book and then trading with another account he makes.

And of course I have talked to the victim and am convinced his account was stolen from. I don't enjoy just blocking random people's accounts. I wouldn't do it unless there really was no other option.