A social network of the Paris terrorists

ParisLike everyone else, I have been following the aftermath of the terrible Paris attacks one week ago. Besides, I am getting increasingly interested in social network analysis, and I read too many crime novels. Combining these things, I have drawn a network combining the different bits and pieces of information available in the media about the people involved in the attacks, and what they did when. The graph above shows a network of actors and events, with the size of the nodes scaled by betweenness centrality.

A few things: Abdelhamid Abaaoud, believed to be the mastermind of the attacks and who died in the raid of the St Denis apartment on Wednesday, appears indeed to have the higher betweenness centrality. The Bataclan attackers (lower left), even if the death toll was the most dramatic, seem to have had a much more peripheral role in the operation. Salah Abdeslam also had an important role in coordinating the different attacks. Finally, through Fabien Clain, a radical Jihadist from Toulouse believed to be the voice in the video claiming responsibility for the attacks, the network is connected to Mohammed Merah, who conducted attacks in 2012, notably against a Jewish school in the Southwest of France.


Terrorisme et asile: un vieux débat

C’est tout de même frappant de constater que les débats actuels sont toujours semblables à ceux du passé.

Journal de Genève, 23 Juillet 1980.Article - ATTENTATS IERRORISTES A PARIS L'asile profané

A map of French terrorist organisations since 1970

Drawing on the Global terrorism Database, I have drawn a network of terrorist organisations having acted on French soil since 1970. The graph above is a two-mode network Organisations x Type of Terrorist Act. The Size of each organisation corresponds to the number of terrorist acts committed, and the size of links corresponds to the number of acts of specific types. A few interesting things: Islamist groups haven’t been the the most active. Corsican independence groups clearly outweigh all others over the whole period, and in the 1980s in particular (the most violent decade in terms of terrorism until now) other groups stand out: Action Directe (Radical Left) and Asala (Armenian group aimed to pressure the Turkish government into recognizing the Armenian genocide).


Paris Attacks: Some Data in Perspective

After the horrible events that happened yesterday in Paris and the mass of instant analyses by more or less reliable experts that swamped the news media, I started wondering whether there was some data out there to put these events in perspective. I had a look at the Global Terrorism Database at the University of Maryland, which compiles all terrorist acts all over the world since 1970. Here are a few graphs drawing on this data.

This is by far the worst terrorist act on French soil. I actually still remember the bombings in Paris by the GIA (Groupe Islamique Armé) in the mid-1990s during the Algerian war, but the number of people killed was only a fraction of what happened yesterday. The number of wounded is also unprecedented. Terrorist acts were however much more frequent in the 1980s. Until this Friday, the most deadly terrorist attack in France was the bombing of the Strasbourg-Paris train on June 18 1961 by the OAS, the paramilitary organisation opposing Algerian Independence, which caused 28 deaths and 100 injured.



The West European country with the biggest number of casualties due to terrorism since 1970  is the United Kingdom. More than 3’000 people died and more than 5’000 were injured in terrorist acts between 1970 and 2014. The Troubles in Northern Ireland were the main responsible for this, but there was also the Lockerbie bombing, in which 243 people died. The second is Spain (ETA, but also the Atocha bombings in 2004).


3. Suicide attacks are completely uncommon in Europe. In terms of people killed, Iraq, Afghanistan, Pakistan and more recently Syria are the countries where the largest number of people die due to suicide attacks. As a share of all terrorist acts, however, suicide attacks are more common in East Asia. The following graphs are based on data for 2011-2014.

SGraph3 Graph2 Graph