Organised criminal gangs are increasingly using rented houses and flats to operate illegal cannabis farms – and police say it is putting the lives of innocent neighbours at risk.

The gangs often use crude methods to bypass electricity meters to avoid paying for the high levels of energy the farms require, creating an increased fire risk.

Rival gangs also carry out raids on each other’s farms – a practice known as ‘taxing’ – carrying out “significant violence” to anyone who gets in their way, police say.

Greater Manchester Police detected 402 cannabis farms between May 2024 and April 2025, and Sky News was given access to an operation by its officers at a semi-detached house in a quiet suburban street in Wythenshawe.

Inside, officers found one room full of cannabis plants and another ‘drying room’ with the drug packaged up and ready to be distributed. The street value was estimated in the tens of thousands of pounds.

Outside, officers found evidence that the electricity meter had been bypassed. ‘Abstracting’ is the offence of dishonestly using, wasting or diverting electricity. One person inside the property was arrested.

“The electricity gets bypassed in order to avoid big electric bills,” Inspector Bree Lanyon said.

“Because a substantial amount of electric is required to run the lights, the ventilation, the heat, everything else that’s required in the cannabis farm, the abstract is done in a haphazard way and it can cause fires within the properties.”

She continued: “We’ve seen a lot of fires recently in premises that have been set up as cannabis farms, because of the way the electricity is set up. It’s not safe and the neighbouring residence could be at risk if that property is burning down.”

The risks posed by cannabis farms were highlighted by the death of seven-year-old Archie York in 2024. He was killed when chemicals being used in a cannabis factory caused an explosion in the family’s block of flats. The drug dealer responsible was jailed for 14 years.

Police say gangs employ low-level operatives, known as gardeners, to manage and protect farms, who will often plead guilty to drug offences and accept the punishment to keep police off the trail of those controlling the operation.

The use of rented properties – sometimes through rogue landlords – also makes detection more difficult.

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“The vast majority are organised crime gangs,” said Detective Inspector Paul Crompton, from GMP’s serious and organised crime group. “It infuriates me when we take action against these farms and people say ‘It’s only cannabis’.

“What we see with cannabis farms is that rival organised crime groups will actively target those and break in and take the products by force. You’ve got a risk of potentially people being kidnapped or killed without us knowing anything about them.

“Make no bones about it, there’s massive amounts of money to make and they would rather just go and take that cannabis and sell it for themselves. They’ll do significant, violence against anybody that gets in the way, whether that’s the gardener, the police or residents who might get in the way.”

Police say landlords need to be aware of the risks and even the chief executive of the British Landlords Association has fallen victim.

One of Sajjar Ahmad’s properties was badly damaged by those using it for an illegal cannabis farm. “I can only explain it as horrific,” he said.

“Our members, when they’ve experienced the problem with the cannabis farm, they are shocked. They didn’t know it could happen. They are not aware of the telltale signs.

“They have the same regrets as what I experienced – you need to carry out regular inspections and, if somebody is offering you a larger rent, then you should question that.”