AS police patrols were stepped up at Scottish transport hubs in the wake of the Brussels bombings a terrorism expert warned that such attacks can and will happen again.

The warning came from Dr Bernhard Blumenau, who lectures in international relations at St Andrews University’s Handa Centre for the Study of Terrorism and Political Violence (CSTPV).

Terror group Daesh was thought to be behind the Brussels attacks, and Blumenau told The National: “The advantage Daesh has is manpower – it has a lot of people who are committed to its cause and it can call on quite easily to plan attacks in European countries, because they have European passports or were born there and can quite easily hide in these places.

“The example of Belgium shows that police and intelligence agencies were not aware that [terror mastermind] Salah Abdeslam was hiding there for a couple of months. I think we have enough evidence that these individuals at least have been travelling in several European countries in order to prepare operations there.

“That shows us there is a risk of these attacks happening and they will probably happen again.”

His warning echoes a similar, chilling alert given by the European Union’s law enforcement agency Europol in January.

It said Daesh cells operating in the EU were largely domestic and locally based, and warned: “The Paris attacks, and subsequent investigation, appear to indicate a shift towards a broader strategy of Daesh going global, of them specifically attacking France, but also the possibility of attacks against other member states of the EU in the near future.”

Abdeslam plotted November’s atrocity in Paris from the Molenbeek suburb of Brussels, and Blumenau said the latest attack was typical of how Daesh operated.

He said: “When Abdeslam was arrested a couple of days ago they apparently found evidence they were planning another attack. So my guess is that this might have been one of the attacks that was planned beforehand and was carried out in a timely fashion following the arrest.”

He said this would serve as a message of retaliation to the authorities, but cautioned that the group was capable of changing its modus operandi.

“The Paris attacks were obviously different from those we have here, where it seems to have been suicide bombers or explosives planted in the metro train, whereas in Paris there were obviously people running around with guns firing at people,” he said.

“They do it in a way that creates most fear and psychological effect on the population.”

He added that there was no easy solution: “There is no answer and one of the things to bear in mind is that in one shape or another there will always be some form of terrorism, because it is a convenient weapon for those who cannot have influence in any other way.”

Blumenau said there was talk about tougher laws to combat terrorism, but that was unnecessary. Instead, he wanted to see the European agencies involved sharing information more efficiently.

“Where there is the biggest room for improvement is having a more coordinated European hub or exchange network where national agencies feed in their information to prevent situations like this.

“The instigators of the Paris attacks for instance had been controlled in Austria and Germany before and the information hadn’t been passed on. The information exchange between the Belgian and French authorities didn’t work very well.

“This shows that even within Brussels the exchange of information between the different police offices does not seem to be working and that’s the biggest area where improvement could be made quite easily.”

The case for further co-operation was reiterated by Àngels Bosch, president of the European Confederation of Police (EuroCOP).

She said: “We must ensure our police forces cooperate in a way they never have before. Recent events have shown us that terrorism knows no borders.

“More than ever before our police forces must cooperate and work together in a manner that recognises this new reality.”

Blumenau added that there was no guarantee the next attack would happen at an airport: “I’m quite sure it will not. It might be a train station a shopping centre, it might be somewhere else because we have all these easy targets and we simply cannot provide a guarantee at any of those.

“A lot of the very visible security at airports I think is also for psychological effect to let people have a feeling of security and safety because there are soldiers or heavily armed policemen there.

“There cannot be any absolute security … this can happen again and I think it will happen again.”

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