Two men from Exeter and a third from Exmouth have been jailed after admitting to growing large quantities of cannabis in a factory-style operation, and selling the drug.
The regional crime squad had uncovered a conspiracy to use Vietnamese nationals to cultivate the plants.
Police found four factories in Exeter, Newton Abbot, Dunkeswell and Minehead, and seized plants worth more than 400 thousand pounds.
A 27 year old Albanian living in Exmouth, Altin Laska, has been sentenced to five years in prison.
Romanians Mircea Rusu who's 24 and 25 year old Nicolae Pasc, both living in Exeter, each received 12 months.
Eight Vietnamese people were also arrested - one has been jailed for 15 months, one is thought to have been trafficked and is being supported, the others are being dealt with by the Immigration system.
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