Access blocking

Information for ASPs

The best option for ASPs (Access Service Providers) wishing to block access to child sexual abuse material is to use a list provided by the national police of domains whose distribution is illegal according to national legislation.

Such a list will reflect national standards in relation to factors such as the age of the victim and type of offence depicted, and will apply national legislation in a precise manner.

For ASPs in countries where this is not possible, the INTERPOL “Worst of”-list of domains will be an alternative.

The decision to participate in this scheme must result from a policy decision within the ASP or be a result of legislation in the country of the ASP.

INTERPOL's list of worst offenders

INTERPOL already supplies a list of domains to countries where the legislation, political or police interest, capacity or manpower are lacking. 

The list provided by INTERPOL is for child sexual abuse material ONLY and it contains the “Worst of”, meaning the most severe child sexual abuse material available on the Web.

The list of domains is compiled on the basis of manual checks by police officers of each included domain. The list is NOT based on search terms or search results, particular words or themes, automatic image analysis or hash values.

INTERPOL has offline versions, for evidence purposes, of all included domains on the list and guarantees that at the time it was seized, the content was in accordance with the strict criteria for inclusion on the list. The content on the default page on any domain may be different to the document the police have seized from the domain. The content in the document initially resulting in the inclusion on the list may have changed at a later time. Reviews of domains where the illegal material has been removed will result in the removal of the domain from the list.

Read more on the criteria for inclusion and general information about the “Worst of”-list of domains.

Protecting children

INTERPOL supplies the "Worst of"-list free of charge and with no obligation to provide statistics or feedback regarding its use.

INTERPOL believes that a policy of redirecting traffic away from severe child sexual abuse material will make this a less profitable business to pursue commercially. Blocking child sexual abuse material in as many networks and countries as possible will dramatically reduce the customer base of child sexual abuse content providers, hopefully to a point where it will no longer be a lucrative business. As a result, fewer children will be commercially exploited on the Web.

The goal of INTERPOL is not to generate cases or investigations into Internet users affected by the blocking and redirection. Rather, the main aim of INTERPOL is to protect the rights of the children depicted in images of abuse by preventing further distribution of these images.

Deleting criminal content

INTERPOL and various national police forces will, in parallel with including domains on the “Worst of”-list of domains, work towards deleting the material from the hosting service.

Making child sexual abuse material unavailable for the Internet user until it is deleted is crucial in preventing distribution.

Equally as important is the time factor: The length of time the files are available to view or download is proportional to the potential added harm to the children depicted and the Internet users who might be exposed to the material.

Digital media like images and films of child sexual abuse are easily copied, multiplied, distributed and hosted in numerous locations. Deletion does NOT necessarily mean eternal removal and is not an easy task when dealing with the Internet.

Hosting may be in non cooperative countries or legislations and there may be automatic copying and moving of the material between domains, hosting companies, countries and continents. In addition, the uploader/distributor of the material will usually have offline versions of the material offered online – ready to be uploaded again.

Child sexual abuse material is normally not co-shared with completely legal material; it usually resides on specific domains created for the sole purpose of distributing the files effectively.

Possessing and distributing files depicting child sexual abuse is illegal in most legislations and the criminals behind the distribution will attempt to avoid detection from law enforcement and hosting companies. The criminal material is distributed by criminals to criminals and/or unwilling viewers.

Therefore, making material unavailable from the “customer” side first, and simultaneously working towards the more time consuming process of having the material deleted, is the most effective way to protect the rights of the children depicted.  This method is also the most effective way to prevent unwanted exposure to child sexual abuse material for the general Internet population.

How to participate

INTERPOL will make the updated list of “Worst of” domains available to National Central Bureaus (NCBs) in its member countries.

The schedule of updates depends on the frequency that new domains are found and seized as evidence by the police, but the list will normally be updated 1-2 times per week.

The list will be in the form of a text file of top level or sub domains, and will not contain illegal content of any kind. When the list is updated centrally from the INTERPOL General Secretariat in Lyon, France, it will be instantly available to all NCBs.

INTERPOL provides a generic agreement to be signed by the NCB and the ASP to define issues such as means of updates and non-disclosure provisions. This proposed agreement is available from the NCB in your country.

INTERPOL also provides a generic "stop page". It is strongly suggested that ASPs use this "stop page" to inform their customers that the Internet traffic has been redirected.

This "stop page" contains links to complaints procedures for Internet users and domain owners, links to further information related to child sexual abuse material and its distribution on the Internet, and links to hotlines to report further material the Internet user may have encountered and considers to be illegal.

ASPs are entitled to add text to this page to reflect the situation in their country, by for instance entering a local hotline that they work with or their own logo and contact information. However, in order to use the INTERPOL "stop page", all original text must remain unchanged. The ASP may use a self-produced "stop page" if they so choose.

There is no obligation to use a "stop page" to be able to receive the list. However, this information is essential for the purposes of increasing transparency and enabling the affected person to request a review and re-evaluation. The "stop page" should be hosted on a server within the ASP’s own network.

If they wish, the ASP may share non identifiable statistics and data, from which IP-addresses and other personal information have been removed, with national police and/or INTERPOL. INTERPOL and/or the national police will use this information to detect and review new and unknown domains that are distributing child sexual abuse material. These domains can then be considered for inclusion in the "Worst of" list of domains.

The "stop page" is available from the INTERPOL NCB in your country.

The ASP is free to use the list they have acquired in one country in networks they may operate in other countries without the need to contact the NCB in those countries.

Contact your country's INTERPOL office

The NCB is your country’s INTERPOL office and is normally located within the headquarters of the national police. ASPs that are unable to find contact information for their local NCB may contact INTERPOL headquarters and your message will be forwarded to the correct NCB.


INTERPOL's International Child Sexual Exploitation (ICSE) database

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