Five people have been arrested in Spain on charges of grooming potential ISIS recruits and funding the organisation in Libya.
In two separate anti-terrorist operations, Spanish national police swept on suspects in Barcelona, Girona, Valencia and Melilla, one of two Spanish cities in North Africa that has a border with Morocco.
Two people were arrested in Melilla for allegedly recruiting young fighters for ISIS.
Police began the grooming investigation, Operation Farcol, two years ago after discovering ISIS indoctrination videos that are believed to have been created and distributed by the two suspects.
Three people were arrested, one each in Barcelona, Girona and Valencia, and charged with helping to fund ISIS in Libya.
The main suspect, arrested as part of Operation Kital, allegedly used a complex network of companies with an international presence to divert funds to a group in Libya with links to ISIS.
He is believed to be related to the leadership of that group.
Five suspected ISIS members were arrested in October last year by Spanish police investigating an alleged attack plot.
Last month, the authorities in Sweden and France launched a joint team to investigate atrocities committed by ISIS against the Yazidi community.
Investigations in the two countries are continuing and are co-ordinated by Europe's crime agency, Eurojust, through the Swedish and French authorities, with the support of the Genocide Network Secretariat, hosted by Eurojust.
Last year, Germany became the first country to convict an ISIS member for genocide against the Yazidi community.