29 March 1992,
Arrest of ETA management in Bidart, Lapurdi. In the joint operation of the French and Spanish police, Francisco Mujika Garmendia Pakito, José Luis Álvarez Santacristina Txelis and Joseba Arrangi Erostarbe Fiti were arrested. They didn't put up resistance.
It was a severe blow to ETA and had to start the restructuring.
Source:
Iñaki Egaña and Giovanni Giacopuzzi, The Days of Algiers: Chronicle of the ETA-Spanish Government Conversations. (Txalaparta)