The movement of drugs and cash in this way is often referred to as ‘county lines exploitation’ because young people are used to move cash and Class A drugs across county boundaries from urban areas into rural towns or county locations. The activity is coordinated by the use of dedicated mobile phone lines. The lure of money is typically used to draw young people into the network.
Further information
Criminal Exploitation of Children and Vulnerable Adults: County Lines (The Home Office) (https://www.gov.uk/government/publications/criminal-exploitation-of-children-and-vulnerable-adults-county-lines) - This guidance outlines what county lines (and associated criminal exploitation) is, signs to look for in potential victims, and what to do about it.
County Lines Violence, Exploitation & Drug Supply (National Crime Agency, 2017)
http://www.nationalcrimeagency.gov.uk/publications/832-county-lines-violence-exploitation-and-drug-supply-2017/file