For ISIS, Barcelona is another trophy to add to tally of attacks on Europe's iconic sites

The deadly attackon locals and tourists walking through Barcelona's Las Ramblas district is part of a strategy on the part of ISIS totargetpopular destinationsin majorcities across Europe and a signal that any major metropolitan area could be hit, say some who have studied similar attacks.

"We know these people [ISIS militants]go for trophies;they go for iconic sites," said Anthony Glees, director of the Centre for Security and Intelligence Studies at theUniversity of Buckingham. "Anybody going to Barcelona goes through Las Ramblas. It is an iconic site.

"It'snot any old place it's a particularplacewith a lot of tourists from all over Europe."

Thirteen people were killed and 100 injured on Thursday when avan was driven through a pedestrian zonein Barcelona's historic Las Ramblas district, swerving from side to side as it plowed into tourists and residents. A second vehicle attack several hours later claimed the life of another person inCambrils, 120 kilometres to the southwest.Spanish policeshot and killed five people they believed were involved in the attacks.

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Authorities have labelled bothincidents as terrorism, and ISIS has claimed responsibility, saying the attack in Barcelona was carried out by "soldiers of the Islamic State" in response to the extremist group's calls for followers to target countries participating in the coalition trying to drive it from Syria and Iraq.

Latest in series of attacks

The Barcelonaincidents markthe latest in a seriesof militant attacks over the past year using vehicles to ram into crowds in cities across Europe. In the southern French city of Nice, 86 people were killedlast July when thedriver of a tractor-trailer targeted Bastille Day revellers.

In December 2016, 12 people died after a driver used a hijacked truck to drive into a Christmas market in Berlin.

In March, a manrented an SUV and plowed into pedestrians on London's Westminster Bridge, killing four people before he ran onto the grounds of Parliament and stabbed an unarmed police officer to death in March.

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And in June, four men drove onto the sidewalk of London Bridge,barrelling into pedestrians and attacking them with knives, leaving eight dead.

"They want to make it seem like the threat is ubiquitous,that it doesn't matter where you go, you could be vulnerable to an attack, that they're everywhere all the time," said Colin Clarke, an associate political scientist at the Rand Corporation, which specializes in insurgency and transnational terrorism.

No city immune

Stratforchief security officer Fred Burton said Barcelona is just another city on the target list for militant attacks.

"There's no city in Europe, quite frankly, that's immune from thesekind of vehicular attacks," he said. "When you look at Spain, it's not immune to these kind of problems."

While Spain has a long history of extremistattacks, primarily from the Basque separatist group ETA, it's been 13 years since a jihadist-related attack.

Thursday's attack was Spain's deadliest since 2004, when al-Qaeda-inspired bombers killed 192 people in co-ordinated assaults on Madrid's commuter trains.

Spain has been atthe second-highest terror alertlevelsince thejihadistattacks againstFrench satirical magazineCharlieHebdoin January 2015, the paper reported.

Asin France and other European countries,ISIS has tapped the country's Muslim population as a source of potentialrecruits who can beindoctrinated and turned intojihadists,saidLorettaNapoleoni, an authorbased in the U.K., U.S. andItalywhohas studied and written aboutterrorism.

"We have a history here also ofradicalization, which makes it easier for whoever wants to carry on an attack to recruit, to find the funds, find the infrastructure, the support," she said.

Spain's Muslim population makes up about four per cent of the population, according to a 2017 demographic study done by the Spanish Union of Islamic Communities (UCIDE), andincludesimmigrants and migrants from North Africa, many of whom have settled inthe Catalonia region, where Barcelona is located. About 42 per cent of Spain's Muslimsare Moroccan nationals and 39 per cent are Spanish, according to the study.

Like other European countries, Spain has also struggled to accommodate the increasing numberofmigrantsentering the country in recent years includingthrough the Spanish enclaves ofMelilla and Ceuta in North Africa.

At least fourofthe suspects identified by police in connectionwith Thursday's attack in Barcelona are of Moroccan origin, with one identified as a Spanish national from Melilla.

'This is going to resonate for months'

"So, you're hitting a majorEuropeancity with a terrorist attackat the height of tourism season. This is going to resonate for months," he said.