Neighbours called police when thieves were spotted trying to break into a house in Bayswater Mount in Harehills in the early hours of Tuesday.

Officers arrived to find a cannabis farm with around 500 plants.

Mains power had been driverted to a hi-tech heating and water system and the main entrance was protected by a metal security gate.

The plants have now been destroyed.

Inspector Nik Adams, who leads the Gipton and Harehills neighbourhood policing team, said: "This was unusual in terms of how we discovered the cannabis factory and investigations are ongoing to find out who set this drug operation up.

"The closure will have a significant impact on the localised drug market and I would urge anyone who has information about those using this house to get in touch with us so they can be arrested and dealt with.

"Cannabis factories are used by organised criminals to fund a number of other illegal activities that are often perpetrated on those living and working in the same area."

He said cannabis factories were also potentially dangerous to neighbouring properties.

He added: "The combination of high amounts of electricity and water can also be extremely dangerous, particularly for those living close by and I ask local people to help us combat this crime by acting as our eyes and ears.

"Cannabis factories can emit a strong and unusual smell and neighbours may hear noises while a factory is being set up. They may also see people coming and going with equipment such as powerful lights.

"It is also likely curtains will be kept closed, but bright lights may appear to be left on around the clock."

Anyone with suspicions is asked to contact police on 0845 606 0606 or call Crimestoppers on 0800 555 111.