The number of sex crimes committed against children in Kent has dramatically slumped.

Last year 495 children in the county were victims of sex crimes, including rape, incest and abuse, according to figures released today by the NSPCC.

But that has fallen by 245, or exactly a third, on the previous year.

That figure is still significantly higher than neighbouring counties: Surrey saw 347 such crimes last year, with Sussex seeing 225 offences committed.

In Kent, 48 of the victims had not reached secondary school age. But the majority of the offences - 447 - were reported against 11-17 year olds.

Julie Cole, NSPCC regional head for South London and the South East, said: "Many of these distressing offences are committed on extremely young and helpless children, who may not understand what is happening to them and are unable to ask for help.

"The NSPCC is doing what it can by using information like this from the police to tailor our treatment services- different approaches are needed depending on the age of the child.

"We are also pioneering new programmes across our region to tackle sexual abuse of children, including our schools service, which aims to visit every primary school in the county over two years.

"But we can’t tackle this problem by ourselves. It requires a major effort from government and the public to give children the protection they need and to provide more therapeutic programmes so the young victims of abuse can start to rebuild their lives."

Nationally, more than 400 sex assaults against children were reported to police forces in England and Wales every week last year (2010-2011) with fewer than one in 10 resulting in a conviction.

Now the charity is calling for a number of measures to tackle the crimes.

The NSPCC wants:

• Schools and parents to educate children about staying safe and reporting abuse.
• Thegovernment to support the provision of therapeutic services for all child victims of sexual offences and treatment programmes for offenders.
• The public to be aware of abuse and how to prevent it.

Children should contact ChildLine on 0800 1111. Last year its volunteers carried out more than 16,000 counselling sessions for children across the UK for sexual abuse.