More than £250,000 of cannabis was found growing in a three-storey house in Low Moor, Bradford.
And the search also uncovered £200 worth of compost that has since been donated to a community group.
Officers for the Tong and Wyke Neighbourhood Policing Team discovered the 500 plant cannabis farm, spread across every room of the property, after receiving a call from local business BAS. Staff had noticed “suspicious activity” on CCTV footage and decided to call police.
On Wednesday evening, officers arrested three men, initially over immigration offences, but there was no information on where the men had come from.
Noticing a nearby house on Short Row had a badly damaged front door, they entered and were then greeted with a house almost filled to the brim with £250,000 of cannabis plants.
Mains electricity to the property had been bypassed, and a team from the Yorkshire Electricity Board were called out to make the house safe to search.
Once it was, it took a team of six officers almost an entire shift to dismantle the farm.
As well as the cannabis they found 35 bags of compost.
Officers decided to donate the fertiliser, valued at £200, to the Springfield Community Garden in Holme Wood to be used for more wholesome plant growing purposes.
A police spokesman said: “Due to the scale of the farm a specialist scenes of crime team were called in to gather evidence and it took a team of six officers the majority of a shift to remove and dismantle the farm.
“A whole host of forensic evidence has been obtained from the address and enquiries are now on ongoing to link offenders to the farm and property.”
On the donation of compost, that was otherwise destined for criminal purposes, Sergeant Mark Otter, from the Tong and Wyke NPT said: “We were pleased to be able to take this fertiliser out of criminal use and give it to a worthwhile project which will benefit the communities of Holme Wood.
“Anyone with information on the cannabis farm is asked to contact the NPT on 101 or Crimestoppers anonymously on 0800 555111.”
One of the men was arrested on suspected immigration offences and the other two on suspicion of cannabis production. They have all been released on bail pending further enquiries.