The Nguyen was paid £200 a month to water and keep watch over 516 plants at a home in North Shields.

When police raided the building on October 11 they found 33-year-old Nguyen with an accomplice sitting on a mattress in the living room.

The rest of the three-storey home in Tynemouth Road had been rigged with ventilators, lighting equipment and a watering system to keep the cannabis plants healthy, Newcastle Crown Court was told.

Nguyen was arrested and admitted cultivating cannabis when he appeared at North Tyneside Magistrates' Court on October 12.

He was jailed for 18 months when he appeared for sentence at Newcastle Crown Court.

Simon Worthy, prosecuting, said the cannabis plants were three weeks away from harvest and could have netted a yield of £90,000.

He said the electricity had been by-passed to keep the infrastructure running.

When arrested Nguyen said he was paid £200 a month to look after the farm, Mr Worthy added.

Tom Moran, defending, said Nguyen was working as a police officer in the border region of Vietnam.

But he found it difficult to feed his family on the performance-related pay scale so travelled illegally to Germany to work.

"Before he could return to Vietnam he was kidnapped by a gang, brought to this country and set to work in this house in Tyneside," said Mr Moran.

"He only realised he had been brought to England when he was questioned by police officers at the station."

Mr Moran added: "The defendant wishes to return to Vietnam and it would cost the tax payer thousands of pounds a week to put him into a prison system that is bursting at the seams."

But Judge Guy Whitburn QC said it would send out the wrong message to impose anything other than an immediate custodial sentence.

Nguyen stood in the dock listening through an interpreter as he was jailed for 18 months.

"This is an extremely serious matter," said Judge Whitburn QC.

"There are a number of cannabis farms in this area and elsewhere run by organised Vietnamese criminal syndicates.

"This was a professional set up.

"The ventilation system, the by-pass of electricity, the lamps and the quantity of plants are all typical of a well financed commercial enterprise.

"I accept you were employed as a 'gardener' and I note that you are not prepared to indicate who employed you.

"It must be clearly understood that anyone in your position will receive a sentence of imprisonment.

"If those who recruited or kidnapped you are able to say to others that they will escape imprisonment for such activity then there is a very high risk of others joining such enterprises."

Nguyen will be immediately deported after serving his prison sentence.