In the space of nine hours in August 2017, a terrorist cell
armed with vehicles and knives launched two attacks on
the city of Barcelona and the town of Cambrils, in Catalonia,
Spain, killing 16 in the worst terrorist atrocity in Spain
since the 2004 Madrid train bombings. New information
obtained by the authors from judicial documents and interviews
with investigators make clear the attacks could have
been much worse. The 10-man cell, which included four
sets of brothers all indoctrinated by an Islamic State-supporting
cleric in the Catalonian town of Ripoll, initially
planned to carry out ambitious vehicle bomb attacks in
Barcelona and possibly Paris using TATP, but changed and
accelerated their plans after they accidentally blew up their
bomb factory. The Islamic State claimed the attackers were
“soldiers of the caliphate,” but while newly disclosed information
shows the network behind the Paris attacks targeted
Barcelona for an attack in 2015, it is still unclear whether
the group had any direct role in the August 2017 attacks.