Catalonia carnage: In one of the worst acts of jihadi terrorism since the Madrid bombings of 2004, a van crashed into a crowd in the Las Ramblas district of Barcelona, killing 13 people and wounding more than 80 on Thursday. The worrying factor is that it doesn't appear to be a "lone wolf", hit-and-run attack — there were two other incidents, north and south of Barcelona, prompting the police to think a wider cell must have been at work.

Police secure the area close to the scene after a white van jumped the sidewalk in the historic Las Ramblas district of Barcelona, Spain, crashing into a summer crowd of residents and tourists Thursday, Aug. 17, 2017. According to witnesses the white van swerved from side to side as it plowed into tourists and residents.

The Islamic State (IS) claimed respondibility, saying it was "a response to calls for targeting coalition states." But Spain had reduced its role in the campaign against the IS and other groups; It withdrew most of its troops from Afghanistan in 2015 and is not part of the air raid against the IS in Iraq and Syria. Catalonia has spain't largest Muslim population, and anti-terror probes have been in focus. King Felipe VI of Spain and Spanish Prime Minister Mariano Rajoy attended a remembrance at Catalonia Square for the victims, comprising citizens from at least 34 countries around the world.