More cannabis farms were found in West Yorkshire than in any other police force area in the country last year, a report has revealed.

Figures for the year up to the end of April, released by the Association of Chief Police Officers (Acpo), show 936 farms were found in the region, equivalent to 42 factories per 100,000 people.

The figure is up from 809 cannabis farms found in the region in 2010/11.

Senior police chiefs said the size and scale of the farms across the UK were falling as criminals were spreading the risk and minimising losses by employing a large number of so-called gardeners to manage small sites across multiple residential areas.

But there has been an increase in the number of farms uncovered, with 7,865 found in the UK last year, up 15 per cent from the year 2009/10.

Over the two years since the last Acpo report about 1.1 million plants have been seized with a street value of £207.4 million.

Bryan Dent, West Yorkshire Police Force Drugs Co-ordinator, said: “This report reflects our pro-active attitude towards all types of drugs including cannabis cultivation.

“It should indicate to the public that we have developed expertise and tactics to act upon the intelligence provided by West Yorkshire communities, and that having received that intelligence, we are content to go into these premises, close them down and take positive action against persons found in the premises cultivating and to investigate the organisers of the farms.”

He said the action on cannabis farms was part of a wider approach to combating drugs, working with partners to reduce demand, restrict supply and help people recover from drug use.

“West Yorkshire is no better or worse that other forces which police large conurbations. What we are good at is recording and retrieving the data and taking positive action against them to make West Yorkshire communities safer places to be in.”

The Telegraph & Argus reported only yesterday a cannabis farm with an estimated 400 plants was discovered in an abandoned shop, Topsys Jewellery in High Street, Queensbury. And last month the T&A reported two men were jailed and faced deportation for their roles in running a £40,000 cannabis factory in Rooley Lane, Bradford.