Spain's Supreme Court yesterday appointed a judge, Eduardo Moner, to investigate allegations that four senior Socialist MPs, including the Prime Minister, Felipe Gonzalez, organised a "dirty war" against Basque separatists in the 1980s.
The court, which has power to lift parliamentary immunity, considered a report by the attorney-general that pointed to "precise, repeated and consistent" evidence implicating the former interior minister, Jose Barrionuevo, in the activities of Gal anti-terrorist death-squads.
It is the first time that a former minister has been officially cited in the scandal that is dogging the final phase of Mr Gonzalez's government.
Mr Barrionuevo said yesterday he was ready to co-operate. "I am ready to appear before the competent authorities straight away and make a statement voluntarily," he said. "They only have to call me."
The attorney-general's report found only "vague allusions" against Mr Gonzalez and "suppositions and value judgements" against the former defence minister, Narcis Serra, and the former Basque Socialist leader, Jose Maria Benegas.
Before yesterday's meeting, a former senior Basque Socialist, Ricardo Damborenea, handed what he said was a blueprint for Gal operations to Baltasar Garzon, the judge investigating a clutch of former security chiefs and senior police in connection with Gal activities.
The photocopied document, which is unsigned but which Mr Damborenea said was written by the security service, Cesid, in July 1993, advocates kidnapping as the best course of action against Eta, murder of Eta members, destabilisation of Eta operations and provoking internal disputes that would look like the settling of accounts.
Cesid's former operations chief, Juan Alberto Perote, said the document was an "office memo".
Mr Gonzalez, on a European tour, said in Moscow late on Wednesday that allegations against him were "pure fabrication" and that he never knew about Gal.