Eight men have been arrested in northeastern Spain, suspected of collaborating with the terrorist organisation that carried out the attacks in Mumbai in 2008.
They are suspected of having connections to radical Islamic cells in Pakistan, linked to al Qaeda.
Media reports allege they belong to a group that steals ID documents which are then sent on to Thailand to be copied and used for illegal purposes.
Seven men of Pakistani origin were arrested in Barcelona on Tuesday. One was arrested on Wednesday. Three other men were arrested in Thailand as part of a parallel operation.
The men are also accused of sending money and fake documents to the militant group Lashkar-e-Taiba, which has been blamed for the assault on Mumbai in November 2008. A total of 166 people died in the attacks.