The number of criminals using ‘county lines’ to spread crime from cities to smaller towns has more than doubled in a year, new figures show.

The National Crime Agency (NCA) says younger people are particularly affected by an increase in criminal gangs from bigger cities expanding operations into smaller towns, using dedicated mobile phone lines and runners to sell their drugs across different regions.

According to the NCA, gangs regularly use violence to drive out local dealers and exploit vulnerable children to sell drugs for them.

Data released by the agency this week said the number of known ‘county lines’ had risen from 720 at the start of 2018 to around 2,000 by January 2019.

Appearing in front of MPs at the home affairs select committee, the NCA’s director of investigations, Nikki Holland, said: “This doesn’t necessarily indicate a worsening of the problem, what it actually indicates is an increasing awareness of law enforcement and our partners to the scale of the problem.”

She warned more than 20 police force areas were now aware of gangs “exporting” drugs to different regions across the country.

More than 600 people were arrested last week in connection with county lines gangs.

Jackie Sebire, a National Police Chief’s Council serious violence co-ordinator, told the committee she believed the amount of violence they were seeing was “a real peak”.

She highlighted an increase in much younger victims across the board and specifically more younger people being murdered.

The NCA says children aged between 15-17 make up the bulk of the vulnerable people involved in county lines, with both girls and boys being groomed and exploited.

Sebire added that even though “one victim is one too many”, serious violence was down by a third from the previous decade.

Iryna Pona, policy manager at The Children’s Society, described the findings as “shocking”.

She said: “Sadly come as no surprise to our practitioners, who encounter the cynical grooming of children as young as 11 by gangs to traffic drugs across the country.

“While children in care or growing up in poverty are often targeted, these perpetrators prey upon any sign of vulnerability, and this exploitation can affect any child in any community, causing unimaginable trauma.

“The progress outlined in this report in disrupting these gangs is welcome, but much more needs to be done to protect these children.”

In October 2018, a drug dealer was jailed for modern slavery offences after being found guilty of trafficking three teenagers from Birmingham in order to expand his drug network.

Zakaria Mohammed had been using county lines to force teenagers as young as 14 to sell drugs.