Sex offenders may be left to walk around because notifications to child protection services are not investigated.

That's according to a support group for child abuse victims, One in Four, which is today launching its 10th anniversary annual report.

It outlines huge progress made in tacking child sex abuse over the past decade.

But Executive Director Maeve Lewis says many tough challenges still remain:

Ms. Lewis says there are practical changes that can be made, but there is a major issue with resources "A full minister for children, a new child & family support agency, a new legislation, but undoubtedly many challenges remain. The HSE child protection services are completely under-resourced and many of our reports to them about sex offenders are not investigated."