RESIDENTS are being urged to look out for tell-tale signs which may mean a house in their street has been turned into a cannabis factory.

Police have closed down more than 20 cannabis factories in the borough and say most are in average streets and rented through letting agencies.

Signs include curtains or blinds permanently closed; large numbers of black bags being removed; tenants visiting the house for only short periods; compost bags and gardening equipment kept near the back door and a pungent smell coming from the property.

Because of the amounts of electricity needed to cultivate the cannabis plants, the houses can become a fire hazard and several have caught fire because of electrical faults.

If you have suspicions about a house in your street, call Bexley police on 020 8284 9170 or Crimestoppers on 0800 555111.

All calls will be treated in confidence.