Three Vietnamese immigrants were sentenced to terms between three and five years in jail for operating the largest indoor cannabis farm in Australia.

In May 2015, Dinh Tung Vu, 27, together with his 30-year-old wife Thi Phuong Lien Tran and his 26-year-old brother Hieu Dinh Vu, were arrested by the police at their home in Alice River in Townsville, Townsville Bulletin reported.

They faced charges of running an indoor “weed”, or cannabis farm that could producet US$2 million worth of cannabis per year. Other charges included possessing hydroponic growing mediums and stolen Ergon Energy equipment.

In April 2017, Dinh Tung Vu and his wife pleaded guilty to the charges. They were given jail terms of five years and three-and-a-half years, respectively, on August 10.

According to his lawyer, Hieu Dinh Vu was unaware of the house’s purpose and he did not even know what “weed” really meant. His lawyer added that his client could not refuse his elder brother’s request to help manage the property. Hieu Dinh Vu was jailed for three years.

Dinh Tung Vu was the chief offender but the operation was so sophisticated that there could be a bigger player behind the scenes who will never be identified, said Judge Gregory Lynham.