Here's what will concern security agencies after the Paris attacks

A policeman stands guard near the Boulevard des Filles-du-Calvaire in Paris. Photo: Thierry Chesnot/Getty Images

The unprecedented sophistication of the multiple attacks in Paris that left at least 120 people dead will raise concerns for intelligence agencies that there may be other well-trained terrorist cells preparing similar plans, a security expert has warned.

A video purportedly from representatives of ISIS has emerged claiming responsibility, and French President Francois Hollande has today blamed ISIS for the atrocity, describing the attacks as an “act of war” by the group.

The nature of the attacks — staged in a major western city and co-ordinated across a sporting venue and well-known social venues with a variety of tactics — suggests a potential escalation in operational capability by ISIS.

Rodger Shanahan, Associate Professor at the Australian National University’s National Security College and a Lowy Institute Research Fellow, said the Paris attacks were characterised by “a degree of complexity that we haven’t seen before”.

With ISIS having suffered some recent “battlefield setbacks” – it lost control of a key Iraqi staging point near Mosul in recent days – Shanahan said the attack may also have been timed to reassert the group’s authority in the media cycle.

He said they showed “not only complexity, but operational security, because it takes a fair bit of planning, and then the ability to conceal their intentions”.

Photo by Thierry Chesnot/Getty Images

Intelligence agencies are increasingly adept at disrupting and exposing extremist plots before they can be executed, so the ability of the perpetrators to conceal their intentions was evidence the attackers were highly organised and well-trained, Shanahan said.

Typically, the final planning phases are a terrorist attack increase levels of “chatter” and surveillance activity among the operations group, increasing the likelihood that they will draw the intention of authorities and have their plans derailed.

The Paris attacks were carried out at seven locations with varying tactics. The most deadly was at the Bataclan venue, where over 100 people were held in apparent hostage situation before gunmen started shooting them one by one, prompting frantic pleas from people inside for police to storm the building. Special forces soon raided the building and killed several gunmen.

Amanda Macias/Business InsiderA map showing where four of the attacks took place.

There were suicide bombings at the Stade de France, where France was playing Germany in football, while there were random shootings at Le Cambodge restaurant and Le Carillon bar in the 10th Arrondissement, and Les Halles shopping center. There were other attacks reported at Rue Faidherbe, Boulevard Beaumarchais, and Rue Albert.

Planning for such an operation would involve heavy co-ordination and logistics requiring advanced counter-intelligence measures to avoid detection.

Shanahan said that if ISIS-trained fighters with experience in the Middle East were behind the Paris attacks, it raised the possibility that similar groups were in place elsewhere.

“This is still evolving but people will be keen to look at who did this – if they’re people who were trained in Iraq and Syria, then there could be other groups out there,” Shanahan told Business Insider. “It shows we’re not dealing with amateurs.”

Police and security agencies would consider this an unlikely method of attack, he said. “When you do planning and analysis, you do planning for the most dangerous. And this is up there with the most dangerous, but in your scenarios this it tends to be less likely.”

A witness to one of the incidents recounted to The Guardian that a gunman he witnessed in one of the attacks in the 10th Arrondissement appeared highly trained:

He was standing in a shooting position. He had his right leg forward and he was standing with his left leg back. He was holding up to his left shoulder a long automatic machine gun – I saw it had a magazine beneath it.

Everything he was wearing was tight, either boots or shoes and the trousers were tight, the jumper he was wearing was tight, no zippers or collars. Everything was toned black.

If you think of what a combat soldier looks like, that is it – just without the webbing. Just a man in military uniform, black jumper, black trousers, black shoes or boots and a machine gun…

He was left handed and shooting in bursts of three or four shots. It was fully intentional, professional bursts of three or four shots.

After more than a year of strong publicity and territorial gains in Syria and Iraq, the march of ISIS dominance in the Middle East has begun to stall.

“They need to dominate the media cycle. Over the past 10 days or two weeks [ISIS] has suffered a number of battlefield setbacks”, Shanahan said. “If you were just looking at the media you might think why you would go and join them.”

Just this week, Kurdish forces re-captured the city of Sinjar, a crucial staging post on the road to the ISIS-controlled Iraqi city of Mosul. Kurdish troops have been celebrating the win with cartoons and memes on social media, claiming it as a humiliating defeat for ISIS.

“I’m sure the planning had been in place but the selection of the timing could have a lot to do with the situation that IS has found itself in over recent weeks,” Shanahan said.

An ISIS strike at this time sent a strategic message, he said. “It’s them saying: ‘You can hit us, but we can hit you back worse.'”

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