More than 100 violent or sexual offenders were reported to Scotland's care watchdog last year, becasue they had been carried out while an offender was on license or statutory supervision .

The Care Inspectorate said it had received 111 serious offence notifications from criminal justice social work departments, about incidents in which someone had reoffended, more than double the number recorded in its previous report on the issue.

However the rise may be partly attributable to local authorities reporting more events including historic ones, to address under-reporting in the past. A previous report criticised councils for a sloppy approach to dealing with the incidents.

The figures cover an 18 month period from June 2013 to January 2015, and 80 of the 111 incidents resulted in serious case reviews. They include cases in which those supposed to be under supervision in the community carried out sexual offences, terrorism offences, homicide, murder or overdosed on drugs.

Social work teams should report any incident in which an offender on license is recalled to custody for an offence causing death or serious harm, a supervised offender has died or been seriously injured or incidents have taken place which raise doubts about the actions taken by professionals working with the offender.

The Care Inspectorate is responsible for ensuring such reviews are carried out and lessons are learned when an incident occurs. It said they highlighted the need for robust risk assessments for offenders, particularly those leaving prison. However the report said councils - of which 24 reported at least one serious incident - had shown willingness to be open about failures and learn from mistakes.

The report makes six recommendations for improvements. These include improved risk assessments for prisoners, after reviews found some prisoners had not been properly assessed in jail prior to release, or if they had the findings had not been passed to social workers.

It warns that it is not acceptable to blame staff shortages or sickness for not carrying out full reviews when something has gone wrong. And it repeats demands that councils comply with government rules on reporting serious incidents. Guidelines state that these should be reported to the Care Inspectorate within five working days, and the findings should be shared with government ministers, but councils only managed this for 36 per cent of serious incidents and on average took two months to report them.

Karen Reid, chief executive of the Care Inspectorate said: “Where an offender is on licence or some form of supervision, there is – rightly – intense public interest in how they are supervised.

“Effective community justice social work can and should prevent re-offending and support offenders to live a life free from crime. Our independent scrutiny of serious incidents and how they were handled is essential to driving up quality and improving public protection.

“If a serious incident occurs, it is always important to consider whether things might have been done better or differently.

"It is critical that serious incidents are reported and reviewed properly and that all criminal justice staff understand and follow the procedures to make sure our communities are as safe as they can be.”

A COSLA Spokesman said: “This report points towards an improvement in local authority practice which should be welcomed. That said, local government is always looking to drive continuous improvement and everyone’s goal would be to reduce the number of serious incidents that take place.

“Local authorities remain committed to reducing reoffending in our communities and this report identifies the need for strong partnership working between agencies in order to achieve this. There will soon be a statutory duty on a range of partners to ensure community justice services are planned collaboratively and outcomes are met at a local level.”