A drugs gang ran a multi-million pound cannabis factory just 50 yards from a police headquarters for months before oblivious officers were alerted to the overpowering smell by a keen-nosed local.

Christopher Bennett, 61, Dale Hart, 53, and Michael Smart, 37, ran the sophisticated operation right under the noses of police officers - who were completely unaware until a nearby businessman reported a strong smell of cannabis.

The gang had turned three industrial units into a huge drugs farm turning over £850,000 every couple of months, just 50 yards from their police station in Bridgend, South Wales.

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A drugs gang ran a multi-million pound cannabis factory just 50 yards from a police headquarters in Bridgend, Wales, for months before oblivious officers were alerted to the overpowering smell by a keen-nosed local

A court heard officers uncovered 692 cannabis plants - worth a street value of £851,621 - growing in a series of plywood rooms built inside the three industrial units.

Prosecutor Stuart McLeese said: 'The drugs operation was discovered after a strong smell of cannabis was reported to police by a member of the public.

'Police forced entry into units 14, 15 and 16 and discovered six internally constructed rooms in each unit and all had electric, water supplies and heat lamps.

'Bennett was found in the office in unit 14 and Hart and Smart were found by the front doors of units 15 and 16.'

Their factory was rumbled by a businessman renting an industrial unit in the same warehouse - and reported them to police just yards away.

Christopher Bennett, 61, (left) and Dale Hart, 53, (right) ran the sophisticated operation right under the noses of police officers - who were completely unaware until a nearby businessman reported a strong smell of cannabis

Newport Crown Court heard the cannabis factory was set up in March 2014 and had operated without detection right next to a busy police station for eight months before being raided in November.

The court heard the set up cost was £25,000 and the men had already produced one lucrative crop of the illegal drug and were about the process their second when they were raided.

Michael Smart, 37, was also involved in the large operation

Mr McLeese said Bennett initially leased the industrial units for use in a legitimate business - until a family tragedy led him to allow a drugs gang to take over the premises.

He said: 'Bennett has pleaded guilty on the basis he took out a lease on units 15 and 16 intending to set up a wood-stripping business with his son as a means to help him recover from drug and alcohol problems.

'His son relapsed and pulled out of the business and Bennett said he couldn't afford to keep up rent. His son's friends stepped in and said they could take over and he allowed them in the full knowledge they intended to grow cannabis.

'His son died in April and Bennett said he was aware of the extend of the operation but wasn't promised any share of the crops or proceeds.'

Bennett claims he was only paid £350 per week and his rent of £1610 per month was paid for by the drugs gang.

Hart admitted hiring the rental vehicles used to transport the drugs and growing equipment and helping cultivate the crops.

Smart also admitted helping to grow the cannabis crop and being paid £300 per week for his work.

Janet Gedrych, defending Bennett, said he had run a successful business in Spain until the financial crash in 2008 and he returned to South Wales.

She said: 'When his son backed out of the wood-stripping project after they were committed to the lease of the units he found himself in a desperate situation and agreed to let his son's friends run a cannabis operation.

The gang had turned three industrial units into a huge drugs farm turning over £850,000 every couple of months, just 50 yards from their police station in Bridgend, South Wales

'He fully regrets now that the drugs that caused his son so many problems - and ultimately caused his death - are still on the streets because of his operation.

'he said when he was arrested he felt nothing but relief as the whole thing had grown far bigger than he ever imagined.'

Judge Eleri Rees told the court: 'It is clear this was a sophisticated operation where a significant investment had been made in equipment and preparing the premises for the growing of cannabis on an industrial level.'

Hart, who also admitted being caught in possession of cocaine, was jailed for five years.