During the peak of Madrid rush hour on the morning of Thursday, 11 March 2004, ten explosions occurred aboard four commuter trains. All the affected trains were traveling on the same line and in the same direction between Alcalá de Henares and the Atocha station in Madrid. It was later reported that thirteen improvised explosive devices (IEDs) had been placed on the trains.
The following time-line of events comes from the judicial investigation.
All four trains had departed the Alcalá de Henares station between 07:01 and 07:14. The explosions took place between 07:37 and 07:40 in the morning, as described below (all timings given are in CET, UTC +1):
Atocha Station (train number 21431) – Three bombs exploded. Based on the video recording from the station security system, the first bomb exploded at 07:37, and two others exploded within 4 seconds of each other at 07:38.
El Pozo del Tío Raimundo Station (train number 21435) – At approximately 07:38, just as the train was starting to leave the station, two bombs exploded in different carriages.
Santa Eugenia Station (train number 21713) – One bomb exploded at approximately 07:38.
Calle Téllez, (train number 17305), approximately 800 meters from Atocha Station – Four bombs exploded in different carriages of the train at approximately 07:39.
At 08:00, emergency relief workers began arriving at the scenes of the bombings. The police reported numerous victims and spoke of 50 wounded and several dead.
By 08:30 the emergency ambulance service had set up a field hospital at the Daoiz y Velarde sports facility. Bystanders and local residents helped relief workers, as hospitals were told to expect the arrival of many casualties. At 08:43, fire fighters reported 15 dead at El Pozo.
By 09:00, the police had confirmed the death of at least 30 people – 20 at El Pozo and about 10 in Santa Eugenia and Atocha.
The total number of deaths was 191. There were victims from 17 countries: 142 Spanish, 16 Romanians, 6 Ecuadorian, 4 Poles, 4 Bulgarians, 3 Peruvians, 2 Dominicans, 2 Colombians, 2 Moroccans, 2 Ukrainians, 2 Hondurans, 1 Senegalese, 1 Cuban, 1 Chilean, 1 Brazilian, 1 French, and 1 Filipino.
The total number of victims was higher than in any other terrorist attack in Spain.
