Governments throughout Europe have expressed fears that foreign fighters in Syria will return to their home countries as committed terrorists with deadly skills and violent intent. How plausible these fears are has been subject to debate. My view is that the fears are well-founded, and that we should no longer be asking whether any European fighters in Syria will return to attempt terrorist attacks, but how many currently have.

To help keep track of open-source information on this, this post provides a list of alleged violent plots in Europe involving people who had joined jihadist groups in Syria. I plan to regularly update the list as more incidents occur, or as more information on these incidents comes out, and may expand the list to include Australia and North America if plots occur there.

To be included in this list, the incident must meet the following criteria: 1. It must involve at least one person who has allegedly returned from fighting with jihadist groups in Syria. 2. It must involve violence or an alleged plan for violence. Simple threats of violence are not included. 3. The violence must have occurred, or been intended to occur, in Europe. This means the many cases of people charged for having fought in Syria, attempting to fight, or supporting fighters, are not included, even if they make some references to wanting to carry out violence in Europe. Also not included is the kidnapping and abuse of European journalists in Syria by British jihadists. 4. The violence or allegedly planned violence must have an apparent ideological motivation. If a returning fighter was to assault someone over an unrelated dispute, it would not be included.

The publicly available evidence for each of these cases varies, and none have seen completed trials. This means that none can be considered definitive, although the Nemmouche case in Belgium looks strong.

For those interested in more information on the Syria blowback, I recommend these articles by Lisa Lundquist and Raff Pantucci, which were useful for this post. Finally, please suggest any incidents I may have missed which meet the above criteria.

List of alleged violent plots in Europe involving Syria returnees:

October 2013: UK police arrested four men and charged them with terrorism offences. They were accused of planning a “Mumbai-style plot” in London, meaning a sophisticated mass shooting of civilians. The men had reportedly returned from Syria, and may have met there. UK authorities have kept a tight hold on information about the case.

October 2013: French police arrested a man named Lyes Darani, allegedly with “a manual explaining how to make a bomb and a letter containing a religious pledge to commit a suicide attack”. A report claimed that he “had just returned from Syria through Lebanon, where he had prepared an attack against Shiites and was inquiring about targets in France for a suicide attack”. He faces a charge involving “criminal conspiracy in connection with a terrorist undertaking”.

November 2013: Police in Kosovo arrested six terror suspects they accused of planning an attack, while a seventh remains at large. Authorities said they had been monitoring the suspected cell for over three months, had gathered evidence through video surveillance, phone tapping, and email monitoring, and had seized firearms and material for making explosives. Two of the suspects, had allegedly fought alongside Syrian jihadists, possibly Jabhat al-Nusra.

March 2014: French police claimed to have foiled an “imminent” terror attack planned on the French Riviera. Earlier in the year, Italian police had arrested, and extradited to France, a 23-year old man who had returned from Syria. He was allegedly caught with soda cans filled with explosives, nails, nuts and bolts. He was also allegedly linked to the Cannes-Torcy cell, which was suspected of planning a grenade attack on a Jewish business in September 2012.

May 2014: Dutch police arrested a 21-year-old man who fought in Syria and was allegedly about to commit armed robbery “to finance jihad”. He faces charges of planning a terrorist attack and illegal firearms possession.

May 2014: A gunman murdered four people near the Jewish Museum of Belgium in Brussels. On 30 May a 29-year old Frenchman named Mehdi Nemmouche was caught, reportedly with guns, ammunition, and a video claiming responsibility for the attack. Nemmouche had also allegedly fought in Syria, with the former al-Qaeda affiliate the Islamic State of Iraq and al-Sham (ISIS). If the allegations prove true, these are the first deaths to occur in a Europe as a result of the foreign fighter flow into Syria.

June 2014: Police in Kosovo arrested three men and charged them with terrorism offences, reportedly involving planned “suicide attacks targeting mass gathering places in order to cause widespread bloodshed and casualties”. The three men had allegedly been recruited by ISIS.

July 2014: A Norwegian police statement said “We also have information indicating that a terrorist action against Norway is planned to be carried out shortly — probably in a few days.” The threat was treated very seriously, with security boosted at potential targets across the country. The plot reportedly involved four ISIS members who left Syria with intentions to attack in Norway or elsewhere in Europe. No one has been charged, but given that there are specific suspects and how seriously the threat was taken, the four suspects would certainly be charged if they were caught.

July 2014: A man named Mohamed Ouharani was arrested in Creteil, Paris. He had reportedly trained with ISIS and was allegedly planning to carry out a shooting attack modeled on the methods of Mohammed Merah and Mehdi Nemmouche. He has been charged under Frances “criminal association” anti-terror laws.

October 2014: Four UK-based men were arrested by counter-terrorism police and have been accused of planning a terrorist attack. Two newspapers claim one of them had trained in Syria with ISIS. However, other reports just say that one of the men “had a connection” to ISIS, not necessarily that he was a Syria returnee. I’m tentatively including this alleged plot in the list until more information comes out.

January 2015: Belgian police raided suspected terrorists, killing two and charging five others. The suspects were allegedly plotting an imminent attack that would target police officers. The raids reportedly uncovered guns, grenades, ammunition, money, police uniforms and chemicals to make TATP (the explosive used in the London bombings). The two dead suspects had allegedly fought with ISIS in Syria.

August 2015: A gunman opened fire on passengers on a train from Amsterdam to Paris, before being overpowered. Some reports say he had returned from Syria, but I have not seen any follow-up on this for a while.

September 2015: French police arrested a man suspected of planning to attack a concert venue. It’s reported that he briefly trained in Raqqa (ISIS’s stronghold in Syria) before injuring himself, then was ordered by camp leaders to return to France for an attack.

November 2015: ISIS-associated jihadists murdered at least 129 people in multiple attacks across Paris. Several of the terrorists are reported to have trained in Syria.

March 2016: Danish police charged a teenage girl and a 24-year old man for allegedly planning a bombing attack in Copenhagen. One of the reported targets was a Jewish school. The man is believed to have fought with ISIS in Syria.

March 2016: Terrorists bombed an airport and train station in Brussels, killing 28 people. One of the suicide bombers who attacked the airport, Najim Laachraoui (who was also the bomb-maker), apparently travelled to Syria in 2013 and joined ISIS. Another suicide bomber, Ibrahim el Bakraoui, is believed to have tried to travel to Syria but was arrested in Turkey and deported.

March 2016: French police arrested a 34-year old man name Reda Kriket for allegedly plotting a terrorist attack. He was reportedly involved with several other suspects, caught with explosives, firearms and fake documents, and had travelled to Syria in 2014 and 2015.

Update 1: This post initially said that the names for the terror suspects in Plot 1 had not been released. However their names had actually been released following a High Court decision earlier this month , though most of the trial will remain secret. In Plot 3 I initially said the suspect was arrested by French police, but he was actually arrested by Italian police in January and extradited to France. I fixed these errors on 30 June 2014, thanks to Raffaello Pantucci for pointing them out.

Update 2: This post initially included the following incident:

June 2014: French police arrested four citizens, two of which had allegedly returned from Syria. They were wanted for “questioning by an anti-terrorism judge for alleged criminal association in view of preparing a terror act”. I have not found any further information, such as what groups in Syria they may have been involved with.

However, Timothy Holman alerted me that it may not meet Criteria 3 (that the planned violent action must be in Europe).

In the French press sources I have the arrests are related to a foreign fighter facilitation network based in Nimes that may have sent up to 20 persons to Syria. See for example http://www.midilibre.fr/2014/06/19/six-ans-requis,1010853.php or http://www.francetvinfo.fr/monde/revolte-en-syrie/deux-jihadistes-francais-arretes-a-leur-retour-de-syrie_625419.html I agree that the use of the term in the English article “It said the four were wanted for questioning by an anti-terrorism judge for alleged criminal association in view of preparing a terror act, without specifying.” suggests a terrorist act but the articles in English and French do not designate a target, nor method of attack etc. In Le Monde, it states, “association de malfaiteurs en vue de préparer des actes de terrorisme” without giving details of attack planning but writing about the number of persons sent to Syria.

I have removed this incident from the list (on 30 June 2014) for now, hopefully more information will come out that clears it up.

Update 3: Added the alleged Norway plot on 22 September 2014.

Update 4: (also on 22 September 2014) I’ve come across three other possible alleged plots, but the information is too thin to conclude they meet the four criteria for inclusion. If any of you have information on the following three incidents, please let me know.

February 2013: An assassination attempt occurred against Danish journalist and Dispatch International editor Lars Hedegaard. The man arrested over it has reportedly fought in Syria. However, from what I can tell his reported involvement with Syrian extremist groups occurred after the assassination attempt, so it may not meet criteria 1. August 2014: A French-Moroccan suspected jihadist was detained at Charles de Gaulle airport in Paris, as part of investigation into a possible “conspiracy to plan terrorist acts”. It’s not clear if he was ever charged. September 2014: Media reports suggest a Dutch couple who had fought in Syria were arrested in Belgium, possibly for plotting an attack on the Berlaymont building, which houses the European Union’s Brussels offices. It does not look like anyone has yet been charged.

Update 5: On 17 November 2014 I added the alleged October 2014 UK plot.

Update 6: (Also on 17 November 2014) Here are another two possible alleged plots, but the information on them is so thin that I’m keeping them out of the list for now.

Late 2013: French police arrested a man named Lyes Darani, allegedly with “a manual explaining how to make a bomb and a letter containing a religious pledge to commit a suicide attack”. A report claimed that he “had just returned from Syria through Lebanon, where he had prepared an attack against Shiites and was inquiring about targets in France for a suicide attack”. It is not clear if he was charged. Now added to list, see Update 8. Thanks to Timothy Holman for alerting me to this article. July 2014: A newspaper reported that a British jihadist had returned from Syria, team up with another UK-based extremist, and plotted an attack that would involve firearms and explosives. It also reported that they remained in contact with a Syria-based controller. However, the report did not give any details about who the man was or what charges he faced.

Update 7: On 23 November 2014 I added the alleged July 2014 France plot. I relied a lot on Google Translate for it though, and would appreciate any further info. I was alerted to this plot by Thomas Hegghammer mentioning it at a recent presentation in Melbourne.

Update 8: On 27 November 2014 I added the alleged Lyes Darani plot, after Jean-Charles Brisard mentioned that he had been charged.

Update 9: On 25 January 2015 I added the alleged Belgium 2015 plot.

Update 10: On 29 September 2015 I added the alleged French concert venue plot. I hadn’t revisited this post for a while, so I suspect I may have missed some cases between January and September 2015, but also wouldn’t be surprised if a couple of the earlier cases have turned out to be less well-founded than first reported.

Update 11: Added the Paris attacks on 17 November 2015.

Update 12: Added the train attack and alleged Cophenhagen plot on 12 March 2016.

Update 13: Added the Brussels attack on 27 March 2016.

Update 14: Added the March 2016 French plot on 2 April 2016. Also, at some point I need to go back through this list and make sure the details remain correct and see if any returnee connections turned out to be false. I don’t know when I’ll get around to that, so if you are planning to use this list in an essay and want something to check it against, I recommend this list of European jihadist plots by Petter Nesser: