A gang which ran a £60 million drug business from a set of isolated farm buildings was heading one of the biggest operations in the country, police said today.
The trade was based at several "highly secure" farm buildings in Swindon, Wiltshire, as well as at an industrial unit near Hungerford, in Berkshire.
The importation and distribution of the cannabis skunk had a "devastating effect" on the lives of thousands of people, Wiltshire Police said.
David Barnes, 41, from Hungerford, Michael Woodage, 51, from Whitchurch, Hampshire, and Christopher Wills, 29, from Bracknell, Berkshire, were found guilty today at Bristol Crown Court following a six-week trial.
A fourth man, Stephen Docking, was acquitted.
Five others, Nigel Hyland, 50, from Laburnum Road, Swindon, Franciscus Kattekamp, 38, from Kaatsheuvel in Holland, Alexander Post, 34, from Belvedere, Kent, Emma Stevens, 39, from Bracknell, and Paul Atkins, 30, from Binfield, Bracknell, had already pleaded guilty to their involvement.
The scheme began to unravel on April 24 this year when Wiltshire Police stopped a van being driven on the M4 travelling towards London.
It was found to contain 50kg of cannabis skunk with an estimated street value of £225,000.
In the early hours of the next day officers stopped a Transit van, being driven by Woodage, on an isolated farm in Wanborough, Swindon, and found it holding 226kg of cannabis skunk with a street value of over £1 million.
Buildings on the farm, which was leased by Barnes, were covered by high-tech security systems and found to contain fork-lift trucks, shrink-wrapping equipment and other drugs-related items consistent with a "distribution centre" set-up.
Ledgers were discovered which linked the farm with the importation and distribution of approximately 10 tons of cannabis skunk with a street value of approximately £60 million in a 14-week period.
Another search was carried out at an industrial unit, leased by Woodage, in Whittonditch, Ramsbury, near Hungerford, in May last year. That also contained equipment usually used to fit out a drug-distribution centre.
As a result of the Operation Scarlet investigation nine people were arrested and charged in connection with the supply of class B drugs.
Following today's verdict Chief Inspector Owen Gillard, who headed the investigation, said: "Operation Scarlet has been the largest operation of this nature in Wiltshire, and is certainly one of the largest drugs operations throughout the United Kingdom.
"The actions of those found guilty today for their role in the distribution of around £60 million worth of cannabis skunk have probably had a devastating effect on the lives of thousands of people all over the country.
"Not only does it destroy individuals' lives but also that of their family and friends. The resulting crime associated with drugs has an even farther-reaching and equally dramatic effect on people, businesses and communities.
"Today's verdicts should send a clear message that we are absolutely determined as a police service to work with partner agencies to tackle the manufacture, production and distribution of drugs and justifies the efforts of our officers and legal team who have worked tirelessly to ensure we have been able to assist the court in reaching its decision.
"We are here to protect the public and are committed to dismantling these organised crime groups.
"We will pursue them through the courts to recover the assets they have made from crime and invest this back into protecting our communities.
"If you are criminally involved in groups like this one you can rest assured that we will catch up with you and we will be knocking on your door."
Sentencing was adjourned until July 23.