Basque separatist group ETA commits one of its most violent attacks, in which a bomb is set off in a supermarket, Hipercor, killing 21 and injuring 45.

ETA, an acronym for Euskadi Ta Askatasuna, was an armed Basque nationalist and separatist organization active in Spain and France between 1959 and 2018. It was founded in 1959, during Francoist Spain, by a group of Basque nationalist students seeking to promote Basque identity and independence. Over time, ETA evolved into a clandestine paramilitary group that conducted a campaign of assassinations, bombings, and kidnappings primarily in Spain, particularly in the Basque Country and surrounding regions. ETA was considered the main organization of the Basque National Liberation Movement and played a central role in the Basque armed conflict, in which more than 850 people were killed, 2,600 were wounded, and nearly 90 were kidnapped. The group announced a definitive end to its armed activity in 2011 and formally dissolved in 2018.