Drug production has increased significantly in recent times in UK's empty high streets as cannabis farms have been cropping up in the most unlikely of places.
Organised crime groups have been targeting empty shops and pubs in town centres to grow cannabis on an industrial scale, say police bosses.
Over the last year, raids have been carried out in dozens of properties, from an old toy shop in Ayr, Scotland, to a former bank in Welshpool, Powys.
Vacant restaurants, cafes, nightclubs, bingo halls and office buildings have all been used to grow the drug, according to the National Police Chiefs’ Council.
In Newport, south Wales, criminals used several floors of a former department store on the main shopping street to grow more than 3,000 cannabis plants.
The street value of the cannabis grown in former store was an estimated two million pounds.
Estate agents, electricians and tradespeople have been warned they face prosecution if they help gangs convert the buildings to cannabis farms.
Chief Constable Richard Lewis said the lack of footfall is allowing criminal gangs to conceal their activities
Chief Constable Richard Lewis, the National Police Chiefs' Council’s national lead on drugs, said the decline of many high streets in recent years has created an opportunity for criminals.
"Commercial properties are attractive to organised crime groups for a whole host of reasons," he explained.
"Large scale shops have closed down and therefore the footprint to produce cannabis on a larger scale becomes available."
Mr Lewis said the lack of footfall during the evening means the cannabis farms can go undetected.
"You don't see large numbers of people in the evening anymore... neighbours in residential properties would notice things more readily," he said.
Last year saw almost 1,000 arrests in operations targeting cannabis farms
Last year saw an intensification of police operations to target cannabis farms, with the issue of 1,000 warrants and nearly 1,000 arrests.
Gwent Police has successfully raided several cannabis farms in Newport city centre, the largest of which was the former Wildings department store which closed in 2019.
"It was done over several floors over many levels, and clearly would have taken some time to set up," said Sgt Dan Wise.
Just over one in six shops in Wales are empty, analysis from the Welsh Retail Consortium shows.
Earlier this year, the police worked with Newport City Council to set up a database of buildings which might be vulnerable to use by gangs.
According to the National Police Chiefs’ Council, forces are being proactive in shutting down the cannabis farms and that does not just mean going after those who grow cannabis.
"We've also prosecuted landlords of these places who at best may be turning a blind eye to what's happening," said Mr Lewis.
Benedicta Bassey with Agency Report