Examining Judge Juan del Olmo on Friday began questioning two suspects linked to the March 11 train bombings in Madrid, judicial sources said.
The sources said Del Olmo was interrogating Faisal Alluch and Khalid Oulad Akcha, arrested last weekend with two other suspects.
The four are all Moroccan nationals.
Del Olmo on Wednesday questioned and remanded in custody Rafa Zuher and Naima Oulad Akcha, the only woman among a total of 18 suspects currently in detention, and the sister of Khalid Oulad Akcha.
Spanish police said on Thursday they had arrested five people, including at least three North Africans, over the bombings that killed 190 people in Spain’s worst terrorist attack to date.
Eleven people arrested two days after the bombings — eight Moroccans, two Indians and a Spaniard — are already in custody facing provisional charges of murder and terrorism after Del Olmo ruled there were grounds to pursue the inquiry.
Two other suspects initially briefly detained — one a Moroccan, the other an Algerian — have since been released. — Sapa-AFP