Over 20 people were arrested during the raids carried out in several provinces in Andalusia, a spokesman for Spain’s Guardia Civil police force said.
Several boats suspected of being used to ship hashish to Spain from Morocco were seized, mainly in the region bordering the Guadalquivir river, which is navigable from the Gulf of Cadiz to Seville, he added.
In a separate operation carried out on Tuesday, Spanish National Police arrested 15 people suspected of belonging to a group based in the southern city of La Linea de Concepcion that provided fuel and food to smugglers who use speedboats to move hashish from Morocco to Spain’s southern coast.
La Linea, an underprivileged city with high unemployment at the edge of the Strait of Gibraltar which separates Andalusia from Africa by just 15 kilometres (nine miles), is the epicentre of the hashish trade.
It is part of the province of Cadiz, which accounted for over half of the 335 tonnes of hashish seized in Spain in 2017, according to the last available figures.