Crimestoppers has launched an innovative campaign to tackle cannabis cultivation by releasing a "scratch and sniff" card which replicates the smell of cannabis.

Wandsworth police will be distributing the cards to the public this week to educate and inform them about the signs to spot and detect cannabis farms by recognising the specific smell of growing cannabis.

The signs to spot cannabis farming include a strong and sickly sweet smell, cannabis growing equipment, constantly covered or blocked off windows, visitors at unsociable hours and lots of cables.

In London. more than 1,200 cannabis farms were identified by police across 2010/2012 - the fourth highest across the UK during that time.