A drone caught out two British men who ran a marijuana farm in a remote area of the Murcia region.
The Brits, aged 48 and 62, bought some land on top of a hill in a rural district of Lorca.
Access was difficult and they cleared trees from their new purchase to set up a marijuana plantation, surrounded by woodland and a ravine.
It was close to impossible to detect the farm at ground level but the men had not bargained for modern technology.
The Policia Nacional were tipped off that the land was being used illegally and they deployed a drone to confirm reports about the farm and its exact location
Armed with visual evidence, officers raided the site and seized 1,100 marijuana plants that had nearly matured.
The arrested Brits are also accused of transporting the finished product to the UK where marijuana prices are up to three times higher than in Spain.