Drug busts in the capital have scattered many organised crime rings to the provinces where they believe they are less likely to be discovered.

Not so.

Police have been cracking down across the county and an unprecedented number of cannabis nurseries or factories have been uncovered.

One Sussex detective said: "They've come to places like Sussex believing the pickings are easier, that there's a ready market and the police are not so active.

"They may be correct believing there is a market here - that goes for almost everywhere in the country nowadays - but they are way off the mark about the police.

"We have had several major busts recently but I imagine there are still plenty of factories out there growing the stuff."

Inspector Dick Myhill at Worthing Police Station said: "In the last 18 months we've had more cases in West Downs than we have done before."

Villains spend hundreds of pounds on hydroponic growing equipment including high-powered lights and sophisticated automatic watering systems.

Much of the equipment can be found on the internet.

Many operations come unstuck when electricity companies suspect power is being stolen or when they find normal consumption suddenly leaps.

One factory was discovered when water pipes leaked.

A former soldier running the operation last month admitted growing hundreds of plants in a huge factory above a shop in Western Road, Hove.

Carlos Perez, from Horsham, admitted producing the Class C drug in rooms above the Paint Emporium in Western Road, Hove. He also admitted possessing cannabis with intent to supply at the same address between January 28 last year and February 3 this year. He will be sentenced later.

Emergency services were alerted by passers by after a hydroponic system used to water and feed the crop sprang a leak.

Water dripped from the rooms housing the operation and started leaking into the shop below. The flood spread across the shop floor and seeped under the front door.

Police discovered rooms above the shop had been knocked together to make two large factory floors.

The hydroponic growing equipment, controlled by timers, provided the plants with water, feed and artificial sunshine. Hundreds of plants in various stages of growth covered the floors.

In other cases neighbours become suspicious about residents behaving oddly or the very strong smell that can escape despite ventilation equipment.

Some factories have been set up in otherwise quiet suburban streets which householders are amazed to discover have been harbouring major drugs operations.

On Tuesday, 600 plants were found in a house in Upper Bevendean Avenue, Bevendean, when the smell prompted a neighbour to tell police they thought there was a dead body on the property.

Householders in the quiet area said they had been concerned about the house, which used to be a hairdressers, since new owners moved in a few months ago. The new occupiers had painted the windows so no one could see in and kept the curtains closed all the time.

Four men, all believed to be originally from Vietnam, were arrested at the scene.

They were assisting detectives with their inquiries yesterday at the police custody centre in Hollingbury, Brighton.

The plants discovered were being taken away by police and ultimately will be destroyed. Samples from the haul have been sent for analysis.

Last year, cannabis plants were found at an address in leafy Southdown Avenue, Brighton, and it was estimated that £30,000 of the drug had been produced in a year.

It took more than 20 officers four hours to empty the attic of its contents. The prosecution was later dropped in court when police lost the accused's files.

In July a factory was uncovered by police checking a tip-off that electricity was being used illegally.

Officers were told the power supply at a house in Croft Road, Hastings, had been tampered with. They noticed a strong smell of cannabis inside the building and found more than 40 cannabis plants a inside a flat occupied by Peter Singer, 35.

Other flats were also being used to grow plants but there was nothing to link Singer to them. Singer was jailed for six months. He admitted producing a controlled drug.

Another major operation was unearthed in April when more than 600 plants were found in an industrial unit.

The factory on the Conqueror Industrial Estate, Castleham, St Leonards, was fitted with automated lights plus feeding and watering systems.

In the same month firefighters called to flooding at a ground floor flat in Mill Road, Worthing, found 60 cannabis plants growing in two rooms on the first floor.

In January 250 plants were found in more industrial units in Elmer, Bognor, and 21 plants were uncovered in Stroud Green, Bognor.