On Friday, the joint Scottish-Spanish operation focused properties in Bellshill, Glasgow, Gartcosh, Whitburn, Caldercruix, Cumbernauld, Coatbridge, Barcelona and in the Malaga space.
Officers made eight arrests in Scotland and 5 in Spain.
Det Ch Insp George Calder instructed BBC Scotland News the investigation was probing alleged high-level involvement in organised crime, medication and cash laundering.
He added: “This day of action has been the result of over two years of investigative work that’s been carried out diligently carried out by officers not only here, but by other agencies, including the National Crime Agency and the Guardia Civil.
“We have gotten quite a lot of officers over in Spain, aiding the Spanish authorities with their inquiries.
“We’re sharing intelligence, information and resources.”
