French and Spanish police arrested Nov. 17 the reputed leader of ETA's commando units — dealing a devastating blow to the armed Basque separatist group.

Mikel de Garikoitz Aspiazu Rubina, 35, is suspected of taking part in several killings, including the December shooting deaths of two Spanish guardsmen in France, according to French and Spanish officials.

Spanish Prime Minister Jose Luis Rodriguez Zapatero said Aspiazu Rubina — known by the alias "Txeroki" — has been the operational chief of ETA's hit squads and bombing units for several years. Aspiazu Rubina was being held in France.

The armed group has been fighting since the late 1960s to create an independent Basque homeland in northern Spain and southwest France.

Aspiazu Rubina's arrest was the most significant since police detained the ETA's alleged overall leader, Francisco Javier Lopez Pena, in May near Bordeaux, France.