ETA, initially blamed for the Madrid bombings that killed 202 people and injured 1,400 others, said it is seeking dialogue with newly-elected Prime Minister Jose Luis Rodriguez Zapatero.
However, ETA said it still reserves the right to use violence in order to achieve its aim of Basque independence, the BBC reported Sunday.
Zapatero has said he wants an end to the 36-year-old campaign by ETA for an independent Basque homeland that has resulted in 800 deaths.
The train bombings are now being attributed to Islamic extremists seeking revenge for Prime Minister Jose Maria Aznar's participation in the U.S.-led coalition in Iraq.
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