Four men were caught by police at a cannabis factory which was about to produce a crop worth more than £2m, a court has heard.


A total of 1,225 cannabis plants were found growing in 10 polytunnels in Black Dyke Road, Hockwold, near Downham Market.


Norwich Crown Court heard the cannabis factory was discovered by police on July 18 this year.


Each of the tunnels held more than 100 mature, 5ft cannabis plants.


The court was told they were to be harvested in the next couple of weeks and would have had a street value of more than £2m.


The prosecutor said three of the four men were found in a caravan at the site, while a fourth man was found in one of the tunnels.


Some tried to escape but all were arrested.


Hoa Van Hoang, 40, Huy Duc To, 40 Huy Than Hoang, 35 and Pham Nam Trung, also known as Thy Tran, 27, all of no fixed abode, appeared at court on Wednesday (November 25) to be sentenced having admitted producing cannabis.


The defendants, all Vietnamese, appeared via video link and spoke through an interpreter.


Jailing the four defendants for a total of four years, Judge Stephen Holt said it was a “very familiar story”.


He said: “Everyone who arrives here from Vietnam illegally appears to have a large debt.”


Judge Holt accepted they were vulnerable and were exploited, having built up debts which they had to pay off.


But he said nothing other than an immediate custodial sentence could be passed and jailed each of them for 12 months.


John Farmer, mitigating for Van Hoang, Than Hoang, and Trung, said all three were in the UK illegally at the time of their arrest.


He said they had come to the county to “pay off pre-existing financial debts in Vietnam” to illegal lenders.


He said all three had worked legitimately until the coronavirus lockdown at which time they were not able to work in the same occupations.


Lynne Shirley, for To, said her client was also in the UK illegally and was likely to be deported back to the country.


She said he had been exploited by others and was fearful of going back to Vietnam as he had been threatened and assaulted.