Lancashire's population contains the largest proportion of registered sex offenders in England and Wales, new figures reveal.
Police forces, probation services and other government agencies keep tabs on dangerous criminals living in communities using special management plans known as Multi-Agency Public Protection Arrangements.
Ministry of Justice figures show 2,250 registered sex offenders were being managed under MAPPA in the Lancashire Police area as of March this year.
That is a rate of 169 offenders for every 100,000 people – the highest in England and Wales, and well above the average of 119.
Sex offenders sentenced to at least 30 months in prison remain on the register indefinitely – although some can apply to be removed after 15 years, following a change to the law in 2012.
Lancashire Police removed nine people from the register following an application last year, with the number of sex offenders growing by 7% from 2018-19.
Across England and Wales, 62,435 sex offenders are being monitored by police – an increase of 4% on 2018-19.
The MoJ said this rise was because of increases in average custodial sentence length and the requirement for many sexual offenders to register for long periods of time.
The vast majority in Lancashire are classed as level one offenders, which means police and other agencies share information about them, but no special measures are required.
But offenders in Lancashire were placed in the level two category eight times during 2019-20, meaning agencies have to hold regular meetings to discuss them, while one was deemed to be level three, the most serious kind.
These offenders pose such a big risk that additional resources such as specialised accommodation may be needed to manage them.
Registered sex offenders have to tell police of any changes to their circumstances, such as their address, foreign travel plans, and potential contact with children.
In Lancashire, 67 offenders were cautioned or convicted for failing to do so last year.
The figures also show that 857 violent offenders – those who have committed crimes such as murder, kidnapping and grievous bodily harm – were living in Lancashire in March.
But this could also include other sexual offenders who are not required to be on the register.
Abigail Gill, policy and public affairs manager at the NSPCC, said: “It’s vital the system is able to manage and monitor these offenders in the community to rehabilitate them and ensure children and young people are protected.
“Sexual abuse has an absolutely devastating impact on young lives and this strategy must focus on prevention and put the experiences and needs of children at its heart.”
The NSPCC is calling for the Home Office's promised Tackling Child Sexual Abuse Strategy to be implemented without delay, urging the Government to ensure it joins up cross-department efforts to prevent sexual abuse across society.
In response, the Government said the national strategy will be published before the end of the year.
A MoJ spokesman said: “We are increasing prison time for the most dangerous sex offenders and when they are released they go on the sex offender register and can be brought back to jail if they break their strict license conditions.
“As sex offenders are required to register for long periods of time, many for life, the number monitored continues to grow as more are caught and convicted.”