Children as young as nine are being targeted by criminal gangs to sell drugs.

Figures disclosed for the first time show that hundreds of children under 16 are arrested each year for dealing drugs and many are picked up by police while they are in school.

Figures showing the number of suspected child dealers arrested has soared by a third from 369 in 2006 to 507 last year.

Teachers unions have warned that the actual number of children being caught with drugs in school may actually be much higher.

The unions say that many cases are dealt with internally and this could lead to them not being documented.

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