Spanish police have arrested five men suspected of forging identity documents and recruiting people for al-Qaeda training camps, officials say.
The men, four Algerians and a Spaniard, were detained on Wednesday and Thursday during raids in Madrid, Barcelona and the northern Basque region.
One of the men is said to have been released after his initial detention.
Officials said the arrests were not linked to the 11 March train bombings in Madrid, which killed 191 people.
A Spanish interior ministry spokeswoman said those arrested belonged to "an infrastructure and support cell suspected of Islamic terrorism that could have recruited people to send to al-Qaeda training camps".
The arrests come as part of an investigation ordered by a Spanish judge, Baltasar Garzon, into suspected al-Qaeda cells operating in Spain.