A cannabis factory with a potential yield of £6 million has been discovered in Soham.
The huge operation - which is believed to be the biggest cannabis farm ever discovered in Cambridgeshire - was uncovered in a derelict industrial unit in Regal Drive.
Officers were on patrol in Fordham Road at around 11pm on Wednesday when they noticed a strong smell of cannabis.
They followed the scent, which took them to the warehouse, believed to be the former Garner Plastics premises.
Officers forced entry and came across approximately 7,000 growing plants, as well as 400 drying plants and 5,000 root balls.
Detective Inspector Dave Murphy said: “This is a significant seizure - certainly one of the biggest, if not the biggest, we’ve ever had in Cambridgeshire.
“It was on an industrial scale. Clearly to have stopped this operation and seized these plants is very pleasing because it means this cannabis will not end up on the streets.”
A police spokesman added: “The potential yield is anywhere from £2 million to £6 million.”
The unit is due to be sealed off tonight (Thursday), with police guarding the cordon.
Officers are due to return tomorrow (Friday) to continue clearing the site.
The discovery has left those working on the industrial estate shocked.
One man who works opposite the site said: “You certainly don’t expect £6 million worth of cannabis to be growing right opposite where you work.
“The grass is cut there regularly - it’s unbelievable that nobody knew it was there.”
One man has been arrested on suspicion of producing cannabis and is currently in custody at Parkside Police Station.
The police spokesman added: “We believe others would have been involved in running such a large production site so enquiries are ongoing.”