Madrid has been one of the most targeted cities by ETA . Prior to the attack , 36 car bombs had gone off in the city in the previous 20 years and at least 119 people had been killed in attacks carried out by the armed organisation . Some of the most important attacks have been a bomb explosion inside a cafeteria on September 13 , 1974 , which killed 13 people , a triple bomb attack on July 29 , 1979 , that killed 7 people , a car bomb explosion on July 15 , 1986 , which killed 12 Civil Guards , as well as two car bombs that killed seven and six army members in 1993 and 1995 , respectively . The Madrid – Barajas airport had also been the location of ETA attacks on July 29 , 1979 , when three civilians were killed , and on August 27 , 2002 , when a car bomb exploded on the second floor of the Terminal 2 parking , causing only material damage , after a warning call from the armed organisation
triple bomb attack
July 1979 Madrid bombings
2006 Madrid–Barajas Airport bombing