29 prisoners, mostly ETA members, fled Segovia prison. They managed to reach the sewer from the yard toilets and out of it. In a truck they moved to Aurizberri, Navarra, near the border, to walk the border with Iparralde. But the limiter was not explained and they decided to cross it on their own. Along the way they met the civilian guards, they started firing and the refugees dispersed.

Catalan anarchist Oriol Solé Sugranyes was killed by the Civil Guard during the flight, without a single stop, with three shots on the back. Only five people managed to cross the border.

Film director Imanol Uribe made the film The Escape of Segovia from these events.