More than 12,000 children under the age of 16 have been arrested for drug-related offences in three years.

Police statistics, released following a request under the Freedom of Information Act, show the scale of young people's involvement with the drug trade.

One case detailed how police in Birmingham investigated a reported burglary in 2008 to find a 10-year-old boy who had turned part of his house into a cannabis factory.

A West Midlands Police spokesman said the boy, now 14, was of "Oriental origin".

"When officers arrived they found parts of the house had been converted into a cannabis factory. [The boy] was arrested on suspicion of the production of cannabis and subsequently charged."

Statisitics revealed that six 10-year-olds were held for possession and 53 11-year-olds detained for possession or intent to sell.

The Metropolitan Police recorded the largest number of arrests, detaining 3,592 children under 16 on drug charges.

One case saw a 10-year-old arrested in Hereford for cannabis possession, although the charges were dropped when the substance was found to be a "legal high".

"These figures underline the importance of early intervention when young people are in trouble or experiencing problems at home or school," said Martin Barnes, of charity DrugScope.

"Sufficient funding for young people's services is key, but many - including drug education and treatment projects - are under threat from local authority cuts."

The age of criminal responsibility is 10 in the UK. A youngster can be convicted if it can be proven that they were fully aware that their actions were illegal.

The data covers 40 out of 43 police forces in England and Wales.