The GAL carried out the attack on the Monbar de Baiona hotel. Four Basque refugees were shot dead in the bar: Agustín Irazustabarrena, José María Etxaniz, Sabin Etxaide and Iñaki Asteasuinzarra.

The inhabitants of the area were persecuted by the killers. As a result, the mercenaries of Marseille, Pierre Frugoli and Lucien Mattei, had to acknowledge their responsibility for the murder and were hired and financed by the Spanish police. They said publicly that they were given two million pesetas for each of the Basque refugees who died.

The attack shocked Basque Country. In Gipuzkoa, a general strike and a day of struggle were held in the other territories of the South. The Kortatu group collected what happened in their song Hotel Monbar.

At least 70 people were killed in the Basque Country during the dirty war.