A GANG who ran a huge cannabis factory and were caught after going for a pizza have been jailed for a total of 18 years.

The four were involved the sophisticated set-up spread over three floors and a 13 rooms at a converted office block in Paisley, Renfrewshire.

Brian Scally (37), Ian Matthews (37), David Kerr (30) and James Robertson (39) were watched by police in January last year.

Prosecutor Duncan McPhie told a hearing at the High Court in Glasgow: “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 of cannabis plants.

The four pled guilty in June to being concerned in the supply of the drug and were sentenced to a combined total of 18 years.

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

“Scully treated this like a job but this was a criminal project.

“Matthews was an electrician working on the premises and you played a part in the operation.

“Kerr was a joiner cementing walls and creating locks for the premises and this was essential works.

“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 heard in June how police swooped at the office block following a tip-off.

The immediately detected a strong stench of cannabis.

Scally, of Linwood, Renfrewshire, 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: “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.

DNA and fingerprints later linked them to the scene.

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

The other three made no comment when initially quizzed.

Mr McPhie told the hearing: “It is understood all had operational roles.

“Matthews performed tasks related to his electrical qualification.”

Scully and Matthews were sentenced to four years each for their involvement.

Kerr and Robertson were handed five-year sentences.

A man in the public gallery shouted: “You’re having a laugh, man” after Kerr’s sentence was readout.