THREE men arrested after the discovery of a multi-million pound cannabis factory in an ex-MOD nuclear bunker have pleaded guilty.

Martin Fillery, aged 45, of Pedwell Hill, Bridgwater, Plamen Nguyen, aged 27, of Bartholomews Square, Bristol and Ross Winter, aged 30, of Maytree Avenue, Bristol, admitted conspiracy to produce class B drugs in Salisbury Crown Court today.

In February officers carried out a midnight raid on an underground nuclear bunker in Chilmark.

RGHQ Chilmark was constructed in the 80s to house local government in the event of a nuclear attack during the height of the Cold War.

The bunker is still intact and police say the nuclear blast doors which were still in place made the site "almost completely impenetrable".

Officers arrested the three men as they were leaving the bunker and keys found in their possession were used to gain entry.

Inside there were over 4,000 cannabis plants inside with the capability of producing £2 million worth of drugs a year.

The men had bypassed mains electricity into the site and had stolen about £250,000 worth of electricity.

Fillery also pleaded guilty to possession of criminal property (money laundering).

The men were previously charged with human trafficking, but the charge has been dropped due to a lack of evidence.

Detective Inspector Simon Pope said: “This was an enormous discovery for our Local Priority Team – I believe it was the biggest cannabis factory we’ve ever had in Wiltshire and the South West region. The isolated and secure nature of the location made the warrant particularly challenging.

“The bunker itself had approximately 20 rooms inside over two floors, and almost every single room had been converted for the wholesale production of cannabis.

"In addition to the growing rooms, there were drying rooms, nurseries and living quarters for the growers – it was a sophisticated set up with an illegal connection to the mains electrical supply.

"The lighting equipment alone seized from the site cost in the region of £140,000 and the set-up was capable of producing a crop every 6 weeks. In all it took approximately 10 days to completely search and clear the site.

“This investigation was a significant undertaking by Wiltshire police into a highly profitable criminal enterprise. I am delighted that the vast amount of preparation to ensure the warrant was executed successfully paid off, and that through the subsequent hard work of the team we were able to bring these three men to justice.

“I’m really pleased that we have been able to dismantle such a large-scale organised operation running in rural Wiltshire – as a result we have stopped an enormous amount of illegal drugs from reaching the streets of Wiltshire and the South West and causing harm to our communities.

“If you suspect drug activity of any scale in your area, please contact police”.

The trio will be sentenced on 11 August 2017.