Counter-Terrorism Internet Referral Unit

(Redirected from Counter Terrorism Internet Referral Unit)

The Counter-Terrorism Internet Referral Unit (CTIRU) was set up in 2010 by ACPO (and run by the Metropolitan Police) to remove unlawful terrorist material content from the Internet with a focus on UK based material. CTIRU works with internet platforms to identify content which breaches their terms of service and requests that they remove the content on a voluntary basis. CTIRU also compile a list of URLs for material hosted outside the UK which are blocked on networks of the public estate.

While action taken to remove content from sites is presumed to be done under website "Terms of Service" (thus requests are unlikely to be clearly reflected in corporate transparency reports) the Home Office definitively refers to all of the removed content as being "illegal".[1]

Legal basis

CTIRU makes an assessment of legality before referring it on to platforms to consider it for removal:

"I underline the fact that any online activity by the three groups under consideration, including Facebook pages and Twitter accounts, has been referred to CTIRU. If it is assessed as illegal — there is a legal test that has to be met — CTIRU will flag it directly to Facebook and Twitter for removal."[2]

CTIRU appear to assess content on the basis of UK terror legislation:

"All referrals are assessed by CTIRU against UK terrorism legislation (Terrorism Act 2000 and 2006). Those that breach this legislation are referred to industry for removal. If industry agrees that it breaches their terms and conditions, they remove it voluntarily."[3]
"I have sat at the shoulder of dedicated officers who surf the web, day by day, with a view to issuing section 3 2006 Act take-down notices" (-- Max Hill)[4]

Such a notice and assessment would provide "actual knowledge" of criminality by a platform, meaning that a platform would no longer be able to rely upon the defence available as part of the E-Commerce Directive that they are an intermediary "hosting" content without an awareness of it. Therefore, although a notice sent by CTIRU to a platform - requesting the removal of content - may request compliance on a voluntary basis, such a notice may also act to ensure that a platform is able to be considered as a "publisher" of the content for the purposes of future legal action if the notice is not complied with.

Scale of CTIRU takedowns and available statistics

Only number of items is reported and requests for more detailed information, such as companies involved, have been denied as "this may provide terrorist groups with useful information"[5], but general numbers have been reported in parliament.

Between establishment in February 2010 and March 2015 it had "taken down 75,000 individual items"[6] and by June 2015 was taking down an average of 1000 "pieces" per week[7].

Ministers continued to report an increase in volumes of takedown in 2016: "Overall, removals at the request of CTIRU have increased from around 60 items a month in 2010, when CTIRU was first established, to over 4,000 a month in 2016."[8]

Some analysis of the kinds of material referred has been made, for instance ministers have claimed that:

approximately 70% of CTIRU’s caseload is Daesh related"[9]

and that:

The unit makes 100 referrals a day related to Syria"[10]

Additionally, the government is able to state that CTIRU have:

developed strong relationships with around 300 companies.[11]

Nevertheless, the Met stated to the ICO and ORG in response to an FOI request that:

The CTIRU do not routinely produce statistics, analysis or evaluations due to the nature of their work. Broadly, their role is focused on identifying and removing content.

The outcome of my enquiries reveal the only report the CTIRU routinely produce is one statistic which does a count of the number of sites/content removed with a time period. (The figure as of today 26/3/2018 is 304,569).[12]

Similarly, in 2017 Sarah Newton, Parliamentary Under-Secretary of State for the Home Department, claimed that a breakdown of CTIRU takedown statistics by service provider could not be given due to “disproportionate cost”.[13]

Parliamentary questions about the number of takedowns by CTIRU usually seem to coincide with the figure increasing by "10,000 pieces of content".

CTIRU Takedown requests per year

CTIRU take downs (approx)
Period (assumed) Takedowns (guess) Total Annual total
Feb 2010 - Mar 2012 Unknown, <3000 Unknown, <3000
Apr 2012 - Mar 2013 3,538 [14] Unknown < 6000
Mar 2013 - Jun 2013 unknown 6000 [15]
Jul 2013 - Sep 2013 500 6500 [16]
Oct 2013 - Dec 2013 11500 18000 [17] over 12000
Jan 2014 - Feb 2014 8000 26000 [18]
Mar 2014 3000 29000 [19]
Apr 2014 - Jun 2014 5000 34000 [20]
Jul 2014 6000 40000 [21][22],
Aug 2014 - Oct 2014 11000 51000 [23][24]
Nov 2014 14000 65000 [25]
Dec 2014 - Jan 2015 7000 72000 [26] 46000 [27]
Feb 2015 3000 75000 [28]
Mar 2015 5000 80000 [29]
Apr - May 2015 10000 90000 [30]
June 2015 5000 95000 [31]
Jul - Aug 2015 5000 100000 [32]
Sep - Nov 2015 20000 120000 [33]
Dec 2015 - Feb 2016 20000 140000 [34] 58000 [35], 55000[36]
Mar 2016 10000 150000 [37]
Apr 2016 10000 160000 [38]
May-Jun 2016 30000 190000[39]
Jun-Aug 2016 10000 200000[40]
Sep-Oct 2016 20000 220000[41]
Nov-Dec 2016 30000 250000[42] 121151[43], (over 120000[44])
Jan-May 2017 20000 270000[45]
June 2017 10000 280000[46]
July-Oct 2017 10000 290000[47]
Nov 2017 10000 300000[48] 50000
Nov 2017 - Dec 2018 0 ? 300000[49] [50]
Dec 2018 - Jan 2019 0 ? "over 250000"[51]
Feb 2019 - Jul 2019 10000 310000[52]

Provider transparency reports

The scale of CTIRU takedown requests is at odds with the numbers of requests recorded and published by Google, Facebook, Twitter and Oath in their transparency reports. These show request volumes as being at most in the hundreds per annum.

Nevertheless, as many CTIRU reports would qualify as simple terms and conditions violations, it is possible that the transparency reports methodologies could disguise the volumes of takedowns. Also, as seen from the Lumen reports, a single CTIRU report may include several URLs, each representing a “piece of content” in the CTIRU figures.

Platform takedown volumes
Period Platform National security takedowns Total government takedown requests T&C violations methodology
Jan-June 2017 Facebook[53] NA 168 Does not include material falling under T&C violations
Jan-June 2017 Google[54] 485 683 Includes T&C violations[55]
July-Dec 2017 Twitter govt ToS reports Global: 154 items 597 accounts 98% compliance Global: 10,626 requests, 6,885 accounts, 31% compliance T&C requests
July-Dec 2017 Twitter[56] NA UK: 94 items; 165 accounts; 20% compliance Non-T&C requests[57]
Jan-June 2017 2017 Oath[58] NA 4 requests, 8 items, 25% compliance Includes T&C requests

Starting in 2017 Twitter provides a combined figure for all government TOS reports, 716, relating to 5,929 accounts, world-wide for the 2016 Q3+Q4.[59] For the period 376,890 accounts were suspended for promotion of terrorism, mostly through Twitters’ own tools.

Twitter terrorism account suspensions (global figures)
Period Takedowns identified by Twitter Total
July-Dec 2016[59] 74% 376,890
Jan-June 2017[60] 95% 299,649
July-Dec 2017[61] 93% 274,460

Lumen database

See also: Counter Terrorism Internet Referral Unit/Lumen reports

A small number of CTIRU requests have been filed to the Lumen database. Around 19 can be found via a simple search.[62]

Lumen shows three reports to Twitter, eight to Google, and eight to Automattic.

10 results can be found on a search for Europol, which operates a similar Internet Referrals Unit.[63] The Europol results are filed by Google and are redacted, leaving just the URL(s) in place.

Social media sites

"In the last 12 months (to the end of June 2015) around 38,889 internet takedowns were undertaken by the CTIRU reducing extremist material available on the Internet. That is over 100,000 since the unit was set up in 2010. Much of this has been achieved by forming working relationships with key social media outlets.[64]"
"CTIRU have developed relationships with over 300 online platforms, and are a YouTube trusted flagger.[65]"
"The CTIRU, for example, are (YouTube) trusted flaggers, and they are extremely qualified experts in this area. They are constantly looking for terror-related videos and flag them to us. We are in constant touch with them—maybe every other week we hear from them. They are able to flag content in bulk to us, and their accuracy rate is around 80%, which is a very high degree of accuracy compared with lower rates in the community more broadly."[66]


"CTIRU have developed and are updating a list of URLs that are hosted abroad and which it is assessed the distribution or hosting of which would (in the absence of any statutory defence) give rise to criminal liability under the provisions of the Terrorism Act 2006. All material filtered from the public estate is therefore considered to be illegal under the Terrorism Act 2006, as assessed by the Crown Prosecution Service (CPS).[67]"
"There is no formal appeal process but if there is concern regarding the filtering of a specific URL containing illegal material, contact should be made with Home Office."

The blacklist, while compiled by CTIRU, is maintained and distributed by the Home Office.

ISP filters

The December 2013 report of the Prime Minister's Extremism task force[68] said that it would "work with internet companies to restrict access to terrorist material online which is hosted overseas but illegal under UK law" and "work with the internet industry to help them in their continuing efforts to identify extremist content to include in family- friendly filters" which would likely involve lobbying ISPs to add the CTIRU list to their filters without the need for additional legislation.

In November 2014 it was announced that [69] BT, Sky, TalkTalk and Virgin Media would incorporate the CTIRU blocklist into their filters.

Nominet domain suspensions

CTIRU is allowed by Nominet to make domain suspension requests. They have so far made one request, according to Nominet’s annual report statistics.

iREPORTit app

In February 2021[70] a mobile (Android/iOS) app iREPORTit, developed by video-analysis company Raven Science, was released for reports to be submitted to CTIRU.


In May 2017 a Home Affairs Committee report [71] recommended that social media companies (such as Google) should required to contribute to the funding of CTIRU.

Questions in parliament regarding the budget and workforce size have been rejected on national security grounds.[72]

Freedom of Information

A request to the Home Office for details of sites taken down was rejected in 2010[73] since ACPO is a private company and not subject to FOIA requests prior to November 2011.

Further attempts to gain information about statistics, costs and possible documentation have been turned down on the basis of national security and crime prevention.

See also

External links


  1. CONTEST, UK strategy for countering terrorism: annual report for 2015, GOV.UK, 2016-07-21 "social media providers removed over 55,000 pieces of illegal terrorist material"
  2. "House of Commons Hansard Debates for 02 Apr 2014 (pt 0003)". 02 April 2014. Retrieved 19 April 2018. 
  3. "Counter-terrorism:Written question - 30893". 14 March 2016. Retrieved 19 April 2018. 
  4. Hansard, 2018-06-26
  5. Hansard, 2015-03-03 - "Since its creation in 2010, CTIRU has secured the removal of more than 75,000 pieces of terrorist and extremist content."
  6. Hansard, 2015-03-03
  7. Hansard, 2015-06-11 - "The counter-terrorism internet referral unit has been, and is now, taking down about 1,000 pieces of terrorist material per week from the internet."
  8. Hansard, 2016-05-04
  9. Hansard, 2016-02-29
  10. Hansard, 2016-05-24
  11. Hansard, 2017-11-01
  12. [Email from the Met to ORG and the ICO, 26 March 2018
  13. Hansard, 2017-03-23
  14. Hansard, 2013-09-23 - "Figures for April 2012 to March 2013 stand at 3,538 pieces of online content removed."
  15. Hansard, 2013-06-26 "Since its establishment in 2010, this unit has removed approximately 6,000 pieces of online terrorist content."
  16. Hansard, 2013-09-23 - "Since the CTIRU was established in February 2010, approximately 6,500 pieces of online content have been removed to date through CTIRU action."
  17. Hansard, 2013-12-12 - "To date ... has removed more than 18,000 pieces of illegal material."
  18. Hansard, 2014-03-10 - "since 2010, it has removed more than 26,000 pieces of illegal terrorist material online"
  19. Hansard, 2014-04-02 - "has taken down more than 29,000 pieces of illegal terrorist material from the internet"
  20. Hansard, 2014-06-19 - "has taken down 34,000 pieces of unlawful terrorist-related content which encourage or glorify acts of terrorism, of which 15,000 have come down since the extremism taskforce concluded in 2013."
  21. Hansard, 2014-07-07 - "has now taken down 40,000 items from the web"
  22. Hansard, 2014-07-30 - "21,000 pieces [since December 2013]"
  23. Hansard, 2014-10-24 - " since December 2013 we have removed from the internet over 32,000 pieces of unlawful terrorist-related content, taking the overall total to over 51,000 since 2010"
  24. Hansard, 2014-10-13 "Since 2013, over 32,000 pieces of unlawful terrorist-related content have been removed from the internet."
  25. Home Secretary Theresa May on counter-terrorism, GOV.UK, 2014-11-24 - "Since the start of this government, the Counter-Terrorism Internet Referral Unit has secured the removal of 65,000 items from the internet that encouraged or glorified acts of terrorism. More than 46,000 of these have been removed since December last year."
  26. Hansard, 2015-01-21 - "It has taken down 72,000 individual items since it was established in 2010"
  27. Hansard, 2016-03-17 "compared with 46,000 in 2014"
  28. Hansard, 2015-03-03 - " Since its creation in 2010, CTIRU has secured the removal of more than 75,000 pieces of terrorist and extremist content."
  29. Hansard, 2015-03-25 - "since February 2010 has secured the removal of more than 80,000 pieces of unlawful terrorist-related content"
  30. Hansard, 2015-06-09 - "Since 2010, over 90,000 pieces of terrorist-related material have been removed at the request of the dedicated Counter-Terrorism Internet Referral Unit."
  31. Hansard, 2015-07-07 - "Since 2010, over 95,000 pieces of terrorist-related material have been removed at the request of the dedicated Counter-Terrorism Internet Referral Unit."
  32. Hansard, 2015-09-14 - "Since 2010, over 100,000 pieces..."
  33. Hansard, 2015-12-02 - "Since February 2010, the Counter Terrorism Internet Referral Unit has taken down more than 120,000 pieces of unlawful terrorist-related content online."
  34. Hansard, 2015-02-29 "Since 2010 over 140,000 pieces of terrorist-related material have been removed by industry from various online platforms at the request of the dedicated police Counter-Terrorism Internet Referral Unit"
  35. Hansard, 2016-03-17 "social media providers removed 58,000 pieces of illegal terrorist material in 2015"
  36. CONTEST, UK strategy for countering terrorism: annual report for 2015, GOV.UK, 2017-06-21 "social media providers removed over 55,000 pieces of illegal terrorist material in 2015"
  37. Hansard, 2016-03-17 "have led to over 150,000 pieces of terrorist-related material being removed to date"
  38. Hansard, 2016-05-04 "have led to over 160,000 pieces of terrorist-related content being removed to date world-wide, including websites, user accounts and videos."
  39. Hansard, 2016-07-12 "Since February 2010, CTIRU has secured the removal of more than 190,000 pieces of online terrorist-related content.
  40. Hansard, 2016-09-08 "HMG has developed strong collaborative relationships with Communications Service Providers (CSPs) which has led to the voluntary removal of over 200,000 pieces of terrorist-related content via referrals from the police Counter Terrorism Internet Referral Unit (CTIRU) since 2010."
  41. Hansard, 2016-10-31 "Since February 2010, internet companies have removed 220,000 pieces"
  42. Hansard, 2017-01-23, "Since it was established in 2010, over 250,000 pieces of terrorist-related material, including websites, have been removed following CTIRU referrals."
  43. Twitter, 2017-01-30 "UK’s Counter Terrorism Internet Referral Unit removed 121,151 pieces of material from the internet by 21 December 2016 - 4x as many as 2015"
  44. Hansard, 2017-03-06 "In 2016 ... secured the removal of more than 120,000 pieces of terrorist-related content."
  45. Hansard 2017-06-28
  46. Hansard 2017-07-04
  47. Hansard 2017-11-01
  48. Hansard 2017-12-07 " since February 2010 300,000 pieces of illegal terrorist material have been removed from the internet."
  49. Hansard, 2018-10-31 "To date, the CTIRU have secured the removal of over 300,000 pieces of terrorist content, including right wing terrorist content."
  50. Hansard, 2018-12-17 " Since February 2010, some 300,000 pieces of illegal terrorist material have been removed from the internet."
  51. Hansard, 2019-01-22, "and has taken down over a quarter of a million pieces of material from the internet."
  52. Hansard, 2019-07-08 - "and have secured the removal of over 310,000 pieces of terrorist material since its inception in February 2010"
  53. United Kingdom, January 2017 - June 2017
  54. Government requests to remove content, UK January 2017 - June 2017 Transparency Report, google,com
  55. Government requests to remove content FAQs “For the purposes of this report, we also count government requests that we review to determine if particular content should be removed for violating a product's community guidelines or content policies.”
  56. Transparency Report, United Kingdom, July - December 2017
  57. Removal requests “It does not include reports submitted by government officials to review content solely under Twitter’s Terms of Service or the Twitter Rules (together, “Twitter’s TOS”). More information about these requests is available in the government TOS reports”
  58. Transparency Report, United Kingdom, Jan-June 2017
  59. 59.0 59.1 Government terms of service reports Jul 1 - Dec 31, 2016,
  60. [ Government TOS reports Jan - Jun 31, 2017],
  61. Government TOS reports Jul - Dec 31, 2017,
  62. Search: CTIRU,
  63. Search: Europol,
  64. Online radicalisation, GOV.UK, 2015-11-26
  65. Hansard 2017-04-21
  66. Oral evidence: Hate Crime and its Violent Consequences, HC 609 Q410, 2017-04-14
  67. FOI #160774, 2013-06-28, Home Office
  68. Tackling extremism in the UK: report by the Extremism Taskforce, GOV.UK, 2013-12-04
  69. UK ISPs to introduce jihadi and terror content reporting button, Guardian, 2014-11-14
  70. Mayor launches mobile app to help Londoners report terrorist content,, 2021-02-24
  71. Hate crime: abuse, hate and extremism online, 2017-05-01, "We believe that the Government should now consult on adopting similar principles online—for example, requiring social media companies to contribute to the Metropolitan Police’s CTIRU for the costs of enforcement activities which should rightfully be carried out by the companies themselves."
  72. Hansard, 2015-03-17 "For reasons of national security we do not publically disclose the detailed allocation of funding for counter terrorism by capability."
  73. Number of websites taken down by Counter Terrorism Internet Referral Unit (CTIRU), 2010-06-14