CHESHIRE police are using their spotter plane fitted with a thermal imaging camera to find cannabis factory heat spots.

They pick up a rooftop glow from the heat generated by the powerful lamps used to grow cannabis.

And the plane has hit the jackpot after pinpointing one of the first significant cannabis factories in the rural area housed within the loft of Woodhouse Farm, Oldcastle, near Malpas, owned by Lord Daresbury’s estate.

On this occasion the plane’s thermal imaging camera picked up heat from a generator in an outhouse which supplied lighting for growing more than 150 plants with a street value of £300,000.

The aircraft is periodically tasked with looking out for such premises but corroborative intelligence is required before police will mount an operation.

Suspicions are believed to have been aroused in this case because of an expensive Bentley care seen coming and going for the isolated rented property.

Because the plants, at varying stages of maturity, were in the loft there was no obvious sign to the outside world – including the owners of the property – about what was taking place inside.

When police attended the scene with a search warrant on Friday they were allowed in by a male occupant who offered no resistance. They were met with the strong smell given off by the cannabis plants.

Crime scene investigators took samples of the plants which have been sent away for analysis to be used as evidence, with the remainder expected to be destroyed.

It is believed two men have been living at the premises for about two years. No link has been made to any other cannabis factories.

Sergeant Andy Smith, of Cheshire Police, who led the operation, said: “Criminals from urban areas, who are involved in the production and supply of illegal drugs, misguidedly believe that isolated rural locations can provide a good cover for their activities. They are wrong. We are always working hard to gather intelligence and disrupt their illegal business, and we shall continue to do so.”

Sergeant Smith expects the price of cannabis in nearby towns to increase given a major element of the supply chain has been removed.

Sgt Smith asked landlords to be pro-active in looking out for suspicious activities taking place at their properties and to contact police. He said Cheshire Constabulary would always act on credible information.

A 34-year-old man from Manchester was arrested at the scene and bailed until February 26. A 63-year-old man, believed to be the younger man’s uncle and from Lincolnshire, was arrested and granted bail until February 21 after handing himself into Blacon Police Station on Tuesday lunchtime.