West Yorkshire Police has revealed it does not know the whereabouts of 11 registered sex offenders – and one has been missing for more than eight years.

Figures obtained under a Freedom of Information (FOI) request to the force told that as of February 12 this year 11 registered sex offenders were wanted because their whereabouts were unknown, with seven believed to be no longer in the country.

And one of the four believed to have remained in the UK has never even registered.

Nationally, 396 sex offenders are wanted, including some who have been missing for more than a decade, according to FOI requests to 39 out of 43 forces.

Registered sex offenders – including rapists and paedophiles – are required to inform police and probation officers of their addresses and are supposed to be monitored by officials working under Multi-Agency Public Protection Arrangements (MAPPA).

Police would not disclosure the dates when the offenders went missing but said the length of time ranged from one week to eight years and nine months.

Six offenders had been missing between one week to four months. A further four have been missing between 14 months up to four years and three months.

The remaining offender had been missing for eight years and nine months, at the time the FOI was produced.

As revealed in the Examiner child sex offences recorded in West Yorkshire have gone up by a third in the past three years.

Police say that due to the nature of the information the total numbers are ‘dynamic’ as enquiries continue.

An FOI Officer for West Yorkshire Police stated in the request: “This total is only valid for the date in question because the information is dynamic and will change as arrests are made or new cases come to light through proactive intelligence-led policing or routine visits to registered offenders. Registered sex offenders are managed in the community by dedicated Public Protection Officers (PPOs) and Public Protection Review Officers (PPROs) who all work within district-based Safeguarding teams.

“A risk assessment is made on each offender to determine the risk level while they are at liberty within the community. PPO’s and PPROs review offenders in accordance with their risk assessment and they are supervised by detective sergeants who will ensure that any breach of the legislation is fully investigated and the offender brought to justice, whenever that is possible. This includes cases where an offender’s whereabouts are unknown.”

West Yorkshire Police did not disclosure names of missing offenders, saying disclosure could help them to evade capture.

Only one of the 11 missing offenders has been publicised to trace the individual via an appeal on BBC Crimewatch.

Anyone with information about any missing registered sex offenders whereabouts can contact Crimestoppers anonymously on 0800 555 111.