Police are appealing for the public's help after one of Kent's largest ever cannabis factories with drugs worth £4million was uncovered at a Dartford office block.

Up to 6,000 cannabis plants were discovered in the derelict building, which had been kitted out with extensive lighting and ventilation equipment.

Electricians had to make St Lawrence House, in West Hill safe before officers could move in yesterday.

The haul was unearthed after a tip-off when someone was spotted clambering into the window.

Police today said it would take anything up to three days just to deal with the 5,000 to 6,000 plants found in rooms in two floors of the property.

Initial estimates suggest the drugs are worth between £2million to £4million on the streets.

Investigating officer, DS Rob Haines from the Kent and Essex Serious Crime Directorate, said: "The sheer size and scale of this operation means people must have been coming and going, and we are appealing to members of the public to search their minds and think of anything suspicious they may have seen around this building.

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"Growing, producing and supplying drugs is against the law.

"Shutting down this factory has taken these drugs out of the hands of dealers and vulnerable members of the community.

"We are following up several lines of enquiry in relation to this discovery and ask anybody who has any information - no matter how insignificant it may seem - to come forward."

Video: Cannabis plants uncovered in a Dartford office block

No arrests have been made, but investigations are on-going.

Chief Constable Ian Learmonth said yesterday: "This is a major drugs supply operation and while we don't yet know whether these drugs were to be used on Kent streets or further afield, stripping down an operation of this size will undoubtedly make a big impact on the county's drug network.

"Keeping these drugs off our streets and out of the hands of dealers and vulnerable persons shows drugs will not be tolerated in Kent."

Officers are expected to remain at the scene for several days as they dismantle the factory and collect evidence.

Anyone with information is asked to call Kent Police on 01474 330506. Alternatively, call Kent Crimestoppers anonymously on 0800 555111.

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