1. The Spanish authorities said that the vehicular attacks that shattered Spain’s summer season appeared to be part of a sophisticated and far-reaching plot that could have resulted in far more devastation.

Fourteen people were killed, and scores injured, in Barcelona and Cambrils. The Islamic State claimed responsibility for both assaults. At least four suspects have been arrested, but the search for the driver continues. Above, mourning the victims in Barcelona.

The authorities linked both assaults to an explosion in Alcanar earlier in the week — a mistake by the plotters, they believe, who had intended to make a powerful truck bomb.