During construction of the Leizarán motorway linking Navarre and Guipúzcoa, the terrorist organisation ETA launched a campaign against the companies involved in the work. Jesús Gallego, chairman of Construcciones Atocha, S.A. was named as a target A., and ETA sent him a parcel bomb. However, the company’s head offices had moved, and the package was returned to the Servitrans transport offices, in the Vallecas district.
Staff at the office realised that the sender’s details were false and notified the National Police’s bomb disposal squad, who arrived at the office shortly after 7 pm on 12 June 1991. The police took the packet to a police van to try to defuse it, but it exploded on the way, killing two of the bomb disposal experts, Andrés Muñoz Pérez and Valentín Martín Sánchez and injuring several other officers and Servitrans employees.
Sub-inspector Valentín Martín Sánchez was a native of Grimaldo (Cáceres), but lived with his wife and two children, aged nine and six, in Móstoles, where he was buried.