It happened on the B3081 near Verwood - he had to be cut free by firefighters.
Drop In Child Arrests In Hampshire And Dorset
There's been a big drop in the number of children being arrested across the South Coast.
Arrests of children by Hampshire Police have fallen by 62% in five years, figures obtained by the Howard League for Penal Reform reveal today (Tuesday 27 May).
In Dorset the drop was 74%.
Research shows that the number of arrests in Hampshire dropped from 10,458 in 2008 to 3,929 in 2013, and from 3,173 to 815 in Dorset over the same period.
The Howard League says it follows a successful campaign aimed at keeping as many children as possible out of the criminal justice system.
Police services across the country have reviewed their arrest procedures and policies as a result of the charity's engagement with them.
However, the charity says despite this positive trend, child arrests remain all too common nationwide - a child was arrested every four minutes in England and Wales in 2013.
Last year, police in England and Wales made 129,274 arrests of children aged 17 and under. These included 1,107 arrests of children who were aged 10 or 11, meaning that on average three primary school-age children were arrested every day.
In 2013 the total number of child arrests was as high as 318,053 - equivalent to an arrest every 99 seconds.
In total, police made more than 1.3million arrests of children between January 2008 and December 2013.
Frances Crook, Chief Executive of the Howard League for Penal Reform, said:
"It is encouraging to see that Hampshire Police are making significantly fewer arrests of children than they were in 2008, thanks in part to our effective campaigning.
"Most police services in England and Wales have developed successful local initiatives that resolve issues quickly and cheaply, involve victims in the justice process and, crucially, avoid criminalising boys and girls.
"A sharp fall in the number of children entering the justice system is good news for everyone striving to reduce crime and saves the taxpayer untold millions.
"The challenge for police now is to maintain this trend. At a time of austerity, further reducing the number of children arrested would free up more officer time to deal with serious crimes."
Children in England and Wales can be arrested by police from the age of 10 - the lowest age of criminal responsibility in Western Europe.
A Howard League briefing paper on the child arrest figures recommends that the age of criminal responsibility should be raised to 14, in line with the European average.
The United Nations Committee on the Rights of the Child has stated that an age of criminal responsibility below 12 is unacceptable.
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