The EU Terrorism Situation and Trend Report (TE-SAT) was established in the aftermath of the 11 September 2001 attacks in the United States of America (USA), as a reporting mechanism from the Terrorism Working Party (TWP) of the Council of the EU to the European Parliament. In 2006 Europol replaced the TWP. The methodology for producing this annual report was developed by Europol and endorsed by the Justice and Home Affairs (JHA) Council on 1 and 2 June 2006.

The content of the TE-SAT is based on information supplied by EU Member States, some third states and partner organisation Eurojust, as well as information gained from open sources.

In accordance with ENFOPOL 65 (8196/2/06), the TESAT is produced annually to provide an overview of the terrorism phenomenon in the EU, from a law enforcement perspective. It seeks to record basic facts and assemble figures regarding terrorist attacks and arrests in the EU. Threport also aims to present trends and new developments identified from the information available to Europol.

The TE-SAT is a situation report which describes and analyses the outward manifestations of terrorism, i.e. terrorist attacks and activities. It does not seek to analyse the root causes of terrorism, neither does it attempt to assess the impact or effectiveness of counter-terrorism policies and law enforcement measures taken, although it can serve to illustrate some of these.

This edition of the TE-SAT has been produced by Europol in consultation with the 2017 TE-SAT Advisory Board, composed of representatives of the past, present, and future Presidencies of the Council of the EU, i.e. Slovakia, Malta and Estonia (the ‘Troika’), along with permanent members, representatives from France and Spain, the EU Intelligence Analysis Centre (INTCEN), Eurojust, the office of the EU Counter Terrorism Coordinator, and Europol staff.

For the preparation of this report, Europol collected qualitative and quantitative data on terrorist offences in the EU, and data on arrests of people suspected of involvement in those offences, provided or confirmed by Member States. As in previous years, Eurojust collected data on the number of court proceedings in each Member State, the number of individuals in concluded court proceedings, the number of convictions and acquittals, the type of terrorism, the gender of defendants, the penalties imposed, as well as the type of verdicts – final or pending judicial remedy. Similar data were collected, when available, of offences in which EU interests were affected outside of the EU. Eurojust contributed data on convictions and penalties for terrorist offences in EU Member States and relevant amendments in national legislation on terrorism.

Included as ‘arrests’ are those judicial arrests warranted by a prosecutor or investigating judge, whereby a person is detained for questioning on suspicion of committing a criminal offence for which detention is permitted by national law. The fact that the person may subsequently be provisionally released or placed under house arrest does not impact the calculation of the number of arrests.

The definition of the term ‘terrorist offences’ is indicated in Article 1 of the Council Framework Decision of 13 June 2002 on combating terrorism (2002/475/JHA), which all EU Member States have implemented in their national legislation. This Framework Decision specifies that terrorist offences are intentional acts which, given their nature or context, may seriously damage a country or an international organisation when committed with the aim of: seriously intimidating a population, or unduly compelling a government or international organisation to perform or abstain from performing an act, or seriously destabilising or destroying the fundamental political, constitutional, economic or social structures of a country or an international organisation.

In cases in which the wording of Article 1 of the Framework Decision leaves room for interpretation, the TE-SAT 2017 respects Member States’ definitions of terrorist offences on their territories. At times, it can be difficult to assess whether a criminal event should be regarded as an act of ‘terrorism’ or as an act of ‘extremism’. Contrary to terrorism, not all forms of extremism sanction the use of violence. Nevertheless, extremism as a phenomenon may be related to terrorism and exhibit similar behavioural patterns. Therefore, the TE-SAT 2017 mentions criminal acts with the potential to seriously destabilise or destroy the fundamental political, constitutional, economic or social structures of a country, when they were reported by the Member States as extremism, in an effort to provide a clearer picture of the phenomenon and its relation to terrorism. However, these cases were not considered in the statistical data of this report, which exclusively reflect incidents reported as terrorism by EU Member States.

The EU Council Decision of 20 September 2005 (2005/671/ JHA), on the exchange of information and cooperation concerning terrorist offences , obliges Member States to collect all relevant information concerning and resulting from criminal investigations conducted by their law enforcement authorities with respect to terrorist offences, and sets out the conditions under which this information should be sent to Europol. Europol processed the data and the results were cross-checked with the Member States. In cases of divergences or gaps, the results were corrected, complemented, and then validated by the Member States.

Amended by the Council Framework Decision 2008/919/JHA of 28 November 2008.

Eurojust also collected data on prosecutions and convictions for terrorist offences on the basis of the aforementioned EU Council Decision. The data used in this report concerns relevant court decisions and legislation amendments in 2016. Due to the specifics of reporting, Member States submit information on both final and nonfinal decisions. Therefore, reference is also made to those decisions pending judicial remedy. Verdicts from 2016 on which an appeal is pending are included in the reporting as pending judicial remedy. In cases where a verdict pronounced in 2016 was appealed, and the appeal was concluded before the end of the year, Eurojust counted the proceeding as one. Eurojust’s contribution was verified with the Member States that provided relevant data.

Types of terrorism

The TE-SAT categorises terrorist organisations by their source of motivation. However, many groups have a mixture of motivating ideologies, although usually one ideology or motivation dominates. It is worth noting that a categorisation of individuals and terrorist groups based on the ideology or goals they espouse should not be confused with motivating factors and the paths to radicalisation. The underlying causes that lead people to radicalisation and terrorism must be sought in the surroundings (structural factors) and personal interpretations (psychological factors) of the individual. The choice of categories used in the TESAT reflects the current situation in the EU, as reported by Member States. The categories are not necessarily mutually exclusive.


Jihadist terrorist acts are those that are committed out of a mindset that rejects democracy on religious grounds and uses the historical comparison with the Crusades of the Middle Ages to describe current situations, in which it is believed that Sunni Islam is facing a “Crusader alliance” composed of Shi’is, Christians and Jews.


Right-wing terrorist organisations seek to change the entire political, social and economic system on an extremist right-wing model. A core concept in right-wing extremism is supremacism, or the idea that a certain group of people sharing a common element (nation, race, culture, etc.) is superior to all other people. Seeing themselves in a supreme position, the particular group considers it is their natural right to rule over the rest of the population. Racist behaviour, authoritarianism, xenophobia and hostility to immigration are commonly found attitudes in rightwing extremists. Right-wing terrorism refers to the use of terrorist violence by right-wing groups. Variants of rightwing extremist groups are the neo-Nazi, neo-fascist, and ultra-nationalist formations.


Left-wing terrorist groups seek to replace the entire political, social and economic system of a state by introducing a communist or socialist structure and a classless society. Their ideology is often Marxist-Leninist. A sub-category of left-wing extremism is anarchist terrorism which promotes a revolutionary, anti-capitalist and antiauthoritarian agenda. Examples of left-wing terrorist groups are the Italian Brigate Rosse (Red Brigades) and the Greek Revolutionary Organisation 17th of November.


Ethno-nationalist and separatist terrorist groups are motivated by nationalism, ethnicity and/or religion. Separatist groups seek to carve out a state for themselves from a larger country, or annex a territory from one country to that of another. Left- or right-wing ideological elements are not uncommon in these types of groups. The Irish Republican Army (IRA), the Basque ETA, and the Kurdish PKK organisations fall into this category.


Single-issue extremist groups aim to change a specific policy or practice, as opposed to replacing the whole political, social, and economic system in a society. The groups within this category are usually concerned with animal rights, environmental protection, anti-abortion campaigns, etc. Examples of groups in this category are the Earth Liberation Front (ELF), and the Animal Liberation Front (ALF).