The Interior Ministry said in a statement Friday that Civil Guard officers in Barcelona arrested 25 people in the operation, which the ministry said was the largest-ever seizure of marijuana in Spain.
The statement says the marijuana was grown and processed in Spain's northeastern region and then taken out of the country by truck. Police believe the gang was led by British and Dutch smugglers.
The gang used front companies to run the cross-border trucking operation, concealing the drugs beneath such goods as sports equipment, home furnishings, animal feed and vegetables.
The statement didn't identify those arrested nor did it say when the arrests occurred.