The investigation into the 30 December 2006 bombing at Madrid-Barajas Airport’s Terminal 4 has advanced after the National Police submitted a detailed report to the Audiencia Nacional, Spain’s National Court. Delivered to Judge Francisco de Jorge, the 176-page report examines whether ETA’s executive committee, known as Zuzendaritza Batzordea (Zuba), had the authority to order the attack during negotiations with the Spanish government. The case targets four former ETA leaders suspected of orchestrating the operation and concerns possible leadership responsibility, separate from the convictions already imposed on the bombers.
The bombing used approximately 200 kilograms of explosives. It killed Ecuadorian nationals Diego Armando Estacio and Carlos Alonso Palate, injured around twenty people and caused extensive material damage. The attack abruptly ended peace talks between ETA and the government led by José Luis Rodríguez Zapatero. The Audiencia Nacional later established that Martín Sarasola, Igor Portu and Mikel San Sebastián, members of the Elurra cell, carried out the attack after receiving the assignment from Garikoitz Aspiazu Rubina, known as Txeroki, in September 2006. In May 2010, the three were sentenced to prison terms totaling 1,040 years. Those convictions addressed the operational perpetrators, leaving open the separate question of whether senior figures authorized or directed the operation.
The victims’ association Dignidad y Justicia (DyJ) has pushed for legal action. It filed a complaint against Jose Antonio Urrutikoetxea (Josu Ternera), Mikel Carrera Sarobe (Ata), Ainhoa Ozaeta (Kuraia) and Airtzol Iriondo (Gurbitz), all believed to have been members of ETA’s executive committee at the time. The police report identifies eight individuals as members of ETA’s leadership in the three months before the bombing. Alongside the four initially named by DyJ, it lists Garikoitz Aspiazu (Txeroki), Francisco Javier López Peña (Thierry), Igor Suberbiola and Iratxe Sorzabal. Thierry died in 2013.
The report describes ETA’s structure as rigid and hierarchical, with centralized decision-making and strict discipline. It argues that operational commands acted as instruments of the leadership’s strategy and that Zuba was responsible for planning and coordinating attacks, as well as authorizing them, particularly those classified as “special operations,” such as the T-4 bombing. Evidence cited in the document includes references to a 2006 meeting in Navarra, where two senior ETA members allegedly instructed three operatives to carry out the Barajas attack. The analysis presents the bombing as a response to stalled negotiations and what ETA regarded as government breaches. The leadership later set out its justification in the organization’s internal publication, Zutabe 112.
Efforts to hold former ETA leaders accountable have intensified in recent years, despite the group’s dissolution and a decline in related court cases. DyJ and specialized police units have pursued cases before applicable limitation periods expired, contributing to the reopening of several proceedings involving more than twenty former leaders. The legal argument under examination is that ETA’s hierarchy and chain of command could support criminal responsibility for leaders who allegedly authorized or directed attacks carried out by subordinate units. In legal terms, this concerns indirect perpetration based on control over the organization. The courts must decide whether that argument applies in the T-4 inquiry.
Other ETA proceedings illustrate the distinction between convictions of direct attackers and investigations into alleged command responsibility. In the separate case over the 2002 Santa Pola bombing, which killed two people, including six-year-old Silvia Martínez Santiago, and injured dozens, proceedings against former leaders were reopened in March 2022 following a complaint by DyJ. The material perpetrators, Óscar Celarain and Andoni Otegi, had been convicted in 2012 and received sentences totaling 843 years. Like the T-4 inquiry, the Santa Pola case examines whether former members of Zuba can be held criminally responsible for attacks attributed to the organization.
Recent judicial decisions also reflect this approach. In January 2025, Judge Francisco de Jorge charged five ETA leaders with responsibility for the 1995 murder of Gregorio Ordóñez, holding them accountable for attacks committed during their tenure on the executive committee. Other rulings have followed similar reasoning, including cases involving the killings of Francisco Arratibel and Miguel Ángel Blanco. In those cases, judges highlighted the leadership’s role in selecting targets and directing operations.
ETA, or Euskadi Ta Askatasuna, was a Basque separatist organization responsible for hundreds of deaths over several decades. The 2006 T-4 bombing ended a ceasefire and peace process. Although the organization ended its armed campaign and formally dissolved in 2018, Spanish authorities continue to pursue unresolved cases. The current investigation asks whether alleged decisions by ETA’s leadership can establish criminal liability independently of the convictions against the operational perpetrators. The answer could affect future cases involving former members of the organization’s command structure.
