The foiled terrorist attack on a Thalys train between Belgium and France on Friday (21 August) has raised questions on train security and surveillance of potential terrorists.

Security measures have been stepped up in European train stations after a gunman tried to shoot passengers of an Amsterdam-Brussels-Paris train. Ayoub El Khazzani, a 25-year old from Morroco, was stopped by several passengers, including US soldiers on holidays, before he could use his AK-47 and automatic pistol. Two people were injured.

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El Khazzani told French police he was "dumbfounded" that he is being accused of terrorism, according to his lawyer.

He said he found the weapons in a park near the train station in Brussels and intended only to rob passengers.

But French president Francois Hollande and Belgium's prime minister Charles Michel agreed on Friday to increase their co-operation on security matters in light of the incident.

Controls

Belgium said it would increase checks and controls on international trains.

But EUobserver’s correspondent, who travelled by Thalys between Paris and Brussels on Sunday evening, did not see any new security deployment.

On Saturday, French prime minister Manuel Valls also announced the the SNCF, the national train company, would launch a hotline where passengers can signal "abnormal situations" in stations and on trains.

Some are asking for stricter and regular controls when accessing trains.

"Having the army in train stations is clearly not dissuasive, we need baggage controls [on international trains] like for the Eurostar”, said Nathalie Goulet, a French senator who chairs an inquiry commission on jihadist networks, in a Twitter post. The Eurostar, which links London to continental cities like Paris or Brussels, operates with passport controls and scanning of luggage and passengers.

But these measures are as much for immigration control as for counter-terrorism, because Britain is not in the passport-free Schengen area.

In Europe, only Spanish high speed trains have installed airport-like controls, after the 2004 Madrid terrorist attacks which killed 191 people.

Fo his part, SNCF chief Guillaume Pepy dismissed the idea of systematic controls.

"The idea of extending the airport system to railway stations today isn't something that I can call realistic," he told the AFP press agency

"Train traffic in France is twenty times bigger than air traffic," he also said in Journal du Dimanche.

Surveillance

Meanwhile, gaps in El Khazzani's profiling and surveillance were revealed over the weekend.

He came to Spain from Marocco in 2007 and was signaled there as a potential threat after he was spotted preaching jihad in a mosque.

He was also filed in France and Belgium.

But while he seemingly moved to Belgium in 2014 or 2015, he was last spotted in May in Germany while boarding a flight to Istanbul. He is also suspected of having travelled to Syria, to fight or to train as a terrorist.

According to the El Pais newspaper, Spanish intelligence informed French colleagues in 2014 that El Khazzani had moved to France.

But French sources and, later, Spain's interior minister denied the information.

El Khazzani was spotted in Germany thanks to the Schengen information system (SIS), but it appears that his moves from one country to another remained under security agencies' radars.

SIS data are shared between national authorities and are not accessible to train or air companies.

The Passenger Name Record (PNR) programme, another EU surveiallace tool, is currently under discussion in the European Parliamenent.

But even if it goes ahead, it would concern only air passengers on international flights, not passengers on intra-EU flights or passengers on intra-EU international trains or buses.