A GANG of cannabis cultivators, featuring two Stevenage men, have been jailed for growing the Class B drug on an industrial scale with the annual yield of their crop estimated to be worth between �973,500 and �2,022,857.

Mark Glencross, 36, was sentenced to three years imprisonment and Desmond Schwartz, 36, received 30 months.

The pair worked with three other men to produce the crop and all five pleaded guilty to offences of conspiracy to produce cannabis and received custodial sentences from Guildford Crown Court on Thursday.

The police operation, code named Operation Tring, was intelligence led and followed an extensive period of surveillance from Surrey Police’s Serious Crime Investigation Team at locations in Hertfordshire, Thames Valley and Cambridgeshire.

The sleuth work led the team to a large warehouse near Cambridgeshire which had been partiality converted to produce cannabis on a large scale.

Around a 40-50m section of the warehouse had been adapted to grow the drug which was filled with rows of plants.

The unit had been equipped with lighting, fans, heaters and air conditioning systems.

Windows had been blacked out with plastic sheeting and there were containers of chemicals that were being used to cultivate the illegal crop.

Raymond Reid, 57, from Constitution Hill, Woking, Surrey, was jailed for six years.

Christopher Morrison, 27, from Luton, Bedfordshire, was jailed for 27 months and Russell Robinson, 37, from Dunstable, received a custodial term of 16 months.