A VIETNAMESE man was kept prisoner in appalling conditions at a cannabis farm in rural Monmouthshire.

Judge Roderick Denyer said the conditions under which Tien Nguyen, 31, was kept as a cannabis farmer were, "as close as you can possibly get to slavery in 21st century Britain".

Nguyen was a cannabis gardener at a barn in Llanvetherine, between Abergavenny and Monmouth, which had been converted for growing cannabis.

But, Newport crown court heard on Friday that Nguyen was effectively a prisoner.

He was locked in and not even allowed out to go to a proper toilet, but forced to use a plastic bag.

Nguyen, a Vietnamese national who has been served with a deportation order, wept as the court was told he only wanted to return home to his wife and four children.

Officers raiding the barn after receiving intelligence found 351 plants and estimated the street value of the potential annual crop at over £260,000.

Judge Roderick Denyer said: "Your story is a terrifying story.

"You were brought to the UK, I have no doubt, to be used as a person to look after and grow cannabis.

"The conditions in whcih you lived at that barn were appalling and effectively you were a prisoner there."

He advised Nguyen that when he returned to Vietnam he should spread the message of what life is really like working for people trafficking gangs.

He sentenced Nguyen to 12 months imprisonment, minus 58 days already served.

Speaking after the trial, PC Mike Brooks of Gwent Police said Nguyen's living conditions were "inhumane".

He said: "The room was about 15ft by 10ft. He had a bed and a stove, some rice and a bucket of drinking water."

PC Brooks said: "These people are victims of a bigger system.

"They often come from a poor background in Vietnam and are led to believe they are going to have a better life and make some money in this country."