A judge has jailed one of three suspected Al-Qaeda members held in Spain earlier this week.
A Turkish suspect was charged on August 3 with possession of explosive materials at the address where he was arrested the previous day in the southern province of Andalucia.
The other two suspects of Chechen origin will be kept in custody while police continue investigations.
They were picked up on August 1 as they traveled by bus toward the French border.
Authorities said the three are thought to have been planning an attack in Europe.
They said the material seized at the Turkish man's flat is thought to be enough to "destroy a bus."
In 2004, an Al-Qaeda-linked bomb attack on commuter trains in Madrid killed 191 people and injured 1,841 others.
Based on reporting by AFP and AP