The latest number of registered sex offenders is to be revealed by the Government.
Last year's figures showed an 18% increase year-on-year.
Home Office data for England and Wales showed there were 28,994 on the list, up 4,422 on the previous 12 months.
Today's figures are expected to rise still further as totals of sex offenders accumulate year-on-year.
Last year's statistics showed 993 registered sex offenders were charged or cautioned for new offences during the year.
Updated figures were due to be published as part of the annual report on so-called Multi-Agency Public Protection Arrangements (Mappa), which bring together police, probation, social services and other agencies to monitor violent and sex offenders in the community once they are released from jail.
In all there were 44,592 violent and sex offenders under Mappa arrangements, according to last year's annual report. The number under "medium" and "high" risk categories rose to 12,765.
This included 1,478 of the so-called "critical few" who are subject to the most intensive supervision and may even be put under police surveillance.
It will be the first annual Mappa report since the system was criticised for its failings in the case of convicted rapist Anthony Rice.
In May this year a report by Chief Inspector of Probation Andrew Bridges highlighted how Rice killed mother-of-one Naomi Bryant just nine months after being freed from a 16-year jail term because officials placed his human rights above protecting the public.
