A new joint unit from the National Crime Agency and GCHQ will target users sharing child abuse images on the “dark net”.
The as-yet-unnamed unit will develop new technological capabilities to analyse the vast array of illegal images and focus on the most prolific offenders.
Prime Minister David Cameron said: “The so-called ‘dark net’ is increasingly used by paedophiles to view sickening images.
“I want them to hear loud and clear, we are shining a light on the web’s darkest corners: if you are thinking of offending there will be nowhere for you to hide.”
The dark net refers to areas of the internet which are not indexed by search engines like Google or Bing. Many sites are only accessible with anonymity software such as Tor.
Around 20,000 people in the UK visit secret or encrypted networks every day, although not all of those who visit these sites do so for criminal purposes.
The dark net is the new focus of a UK campaign against child abuse images which has had notable success on the “surface web”.
In 2014, the Internet Watch Foundation, which proactively seeks out child sexual abuse imagery, has removed images from 27,850 websites – a 109% increase on the previous year.
In 1996, the UK was responsible for 18% of all child abuse imagery hosted online. Today, it is responsible for only 1%.
Private companies have helped with this effort. Images identified by the Internet Watch Foundation are given a digital fingerprint, called a hash value.
Google, Microsoft, Twitter, Facebook and Yahoo use those fingerprints to identify images being shared on their sites and to remove them.
Google and Microsoft have also introduced changes to their search engines. Microsoft uses information provided by the NCA to black list particular search terms.
Matt Brittin, Google’s president for northern and central Europe, said: “Over the past 12 months our algorithm changes and deterrent campaign have already led to a five-fold reduction in a number of child sexual abuse image-related queries in search.”
The new unit is the cornerstone of measures to be announced by Mr Cameron at the We Protect Children Online summit in London.
The UK has created its own database of 2.6 million known child abuse images to assist police across the country.
More than 30 countries have given commitments to increase their law enforcement endeavours around online child abuse, by setting up their own national databases of child abuse material or linking to the Interpol database.
A new 50 million Child protection Fund, the first of its kind, will support prevention and help victims. UNICEF will support its development.