The finca in Morón de la Frontera 63km southeast of Seville contained over 3,000 cannabis plants as well as a “sophisticated artificial air-conditioning system which created the ideal conditions for their cultivation,” the Policía Nacional said in a press release.

Heat lamps, moisture sensors, weapons and high-end vehicles were also seized from the plot. Seven people accused of being members of the criminal organization which ran the plantation and distributed the produce have been arrested.

The raid was the culmination of an investigation which involved the collaboration of local residents, who alerted police to the possibility of an indoor marijuana farm being present on the estate.

After surveying the site, police investigators verified the existence of what they believe to be an organized criminal network led by a man who is said to have controlled the operation from his home, with marijuana the principle crop. The man is also suspected to have employed a team in charge of growing, collecting, preparing and distributing the narcotics.

Police explained that the plantation was hidden within the estate, and as such “advanced technical methods” were necessary to detect unusual sources of heat on the property which are typical of cannabis cultivation.

Five people working on the farm were arrested when it was raided, while two others were later detained. Three high-end vehicles, two shotguns and 700 shotgun shells were taken from the property, while the plantation containing more than 3,000 marijuana plants, 400 heat lamps and a sophisticated air-conditioning unit was dismantled.

The seven individuals arrested – some of whom already had a criminal records – now face accusations of drug trafficking offences, defrauding of electricity, membership of a criminal organization, illicit possession of arms and breach of sentence.

It was not a clean sweep for officers however: the leader of the organization and his partner managed to escape in a sports car following a high-speed chase from police who had attempted to arrest them. The investigation remains open as a result.