Quoted from openparliament.ca on 2018-03-26
The same principle is used for guns: there are computer protocols that allow users to carry out transactions in hidden parts of the Internet. We have also heard about cryptocurrencies such as Bitcoin, which are almost impossible to trace. Criminal gangs use them to buy guns, which they are smuggling in ingenious ways. For example, they will hide a handgun in an Xbox console to get it through customs.