Police have raided a cannabis factory in Surbiton and uncovered four rooms filled with the illegal plants.

They had intelligence on a Balaclava Road address and a heat-seeking helicopter confirmed suspicious activity in the house.

The helicopter pilot reportedly said the three-bedroom cottage was giving out so much heat he could have warmed his hands on it.

“These sort of factories are becoming more common, especially in residential areas where there is a lot of property to let,” said Sergeant Robbie Manns.

At approximately 7.20am on Friday two of officers entered The Lamb pub garden at the back of the property, in case anyone bolted, and EDF Energy were on hand to assess the safety of the front door.

“We have to check its not wired as offenders sometimes booby trap the place,” said PC Lee Playden. “It’s not just to protect it from the police but from rival gangs who might try break in.”

Air fresheners and candles were lined up on a radiator by the front door, in an attempt to disguise the potent smell, and a saucepan of scented wax was in the kitchen.

One room downstairs contained an estimated 75 plants and the floor space of three upstairs rooms was completely filled.

The electricity meter had been cut to avoid suspicion but the heat coming off a 100 amp fuse removed from the house gave an idea of the amount of the electricity being used.

A neighbour, who did not wish to be identified, said: “There’s been no life in the house for ages. I did see an Asian guy go in there once with bags of shopping but didn’t think much of it. I’m so shocked.

“They did a good job keeping it quiet, we’re up all hours of the day and never saw a thing. Surbiton is a quaint town and the last thing you expect is to have your neighbour’s door broken down.”

The house was empty in January and police said bags of old leaves provided evidence of previous crops.

“It’s quite a big find and now we can work on finding the people behind it,” said Sgt Manns.

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