The number of children arrested over drug dealing surged by more than a quarter over the past five years.
A total of 1,639 under-18s were detained for possession with intent to supply or supplying drugs in 2013, compared with 2,097 in 2017.
Children as young as 12 were reportedly arrested for possession with intent to supply drugs such as heroin and crack cocaine.
The figures, obtained by the Guardian cover 24 of the 43 police forces in England and Wales.
The findings raised concerns over young people being exploited by gangs to sell drugs in out-of-town areas – a practice known as “county lines”.
DS Ken Lamont, of Devon police, told The Guardian that county lines trading was a contributing factor in the rise in arrests.
“At the moment I wouldn’t say it is endemic but it’s certainly a problem and we have done significant disruptions,” he said.
Rhiannon Sawyer, the Children’s Society’s area manager for children and young people’s services in Greater London, told the paper her staff had noticed more children being targeted to deal drugs, some as young as 12.
“They are more vulnerable as they are younger and the rise is significant enough to get us worried about it,” she said.
“The level of violence is getting worse.”