Spanish officials say they thwarted a second terrorist attack after 13 people were killed when a van plowed into pedestrians in Barcelona's famous Las Ramblas tourist area on August 17.
Hours after the Barcelona attack, police said they shot dead five "terrorists" as they staged a similar attack in the seaside town of Cambrils, south of Barcelona.
Six civilians and a policeman were injured in Cambrils, where police said they would carry out controlled explosions as the dead suspects were wearing explosive vests.
Dozens of people were also injured, some critically, in Barcelona when the van swerved at high speed through a crowded pedestrian walkway in an attack claimed by the Islamic State extremist group.
Spanish authorities said people from at least 18 countries mostly in Europe, including Macedonia, were among the victims.
Shortly after the attack, police arrested two people, a Spanish national and a Moroccan, but said the van's driver escaped and was still on the run.
Police said the van attack was linked to an explosion at a house in Alcanar earlier in the day that killed one person and injured another as they were making explosives.
Spanish Prime Minister Mariano Rajoy said "the terrorists will never destroy a united people who love liberty over barbarism."
In the past year, vehicles have been used to ram into crowds in a series of militant attacks across Europe, killing more than 100 people in Nice, Berlin, London, and Stockholm.