FOUR members of a gang which ran a huge cannabis factory from a converted office block have been jailed for a total of 18 years.

The quartet were involved in a sophisticated set-up spread over three floors and 13 rooms of the building in Glasgow Road, Paisley.

The High Court in Glasgow heard that Johnstone man David Kerr, along with Brian Scally, of Linwood, and Ian Matthews and James Robertson, both of Paisley, were being watched by police in January last year.

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Prosecutor Duncan McPhie said: “Police recovered CCTV footage from a branch of Pizza Hut nearby. This linked the four to the scene, showing them entering and leaving.”

Officers soon raided the premises and seized £430,800 worth of cannabis plants.

In June, the four admitted being concerned in the supply of the drug.

Sentencing the gang yesterday, judge Lord Clark said: “You have pled guilty to a serious charge.”

The court was told that Scully treated his involvement in the operation as being “like a job,” while Matthews was “an electrician, working on the premises.

Kerr was said to be a joiner who cemented walls and created locks for the premises, described as “essential works.”

Lord Clark added: “Robertson’s role was to look after the plants, as he was a landscape gardener and was fundamental for this type of enterprise.”

The court previously heard how police swooped at the office block following a tip-off and immediately detected a strong stench of cannabis.

Scally, 37, blurted out: “It is not mine. I just work here.”

Police went on to find a total of 718 cannabis plants in 13 different rooms.

Mr McPhie said: “The growing operation was sophisticated, with fans, ducting, lighting and other associated items of equipment.”

Extra power sockets had been fitted and windows were covered with reflective panels.

Police believed it would have cost £50,000 to set up.

The court heard officers also got CCTV footage from the nearby Lagoon Leisure Centre, which further pinned the four.

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DNA and fingerprints later linked them to the scene.

Scally told police he had been paid £300 per week to “tend” to the plants.

Kerr, 30, Matthews, 37, and 39-year-old Robertson made no comment when initially quizzed by officers.

Scully and Matthews were sentenced to four years each for their involvement, while both Kerr and Robertson were handed five-year terms.

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