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Marijuana-scented cards to help track down cannabis farms

19 March 2013 Last updated at 12:27 GMT

Marijuana-scented scratch-and-sniff cards are being posted to hundreds of households in a bid to detect illegal cannabis farms.

Crimestoppers, which runs the campaign, said the cards would help people to recognise the smell of cannabis and report suspected plantations to police.

The charity said there was a 15% rise in the number of cannabis farms found in homes between 2011 and 2012.

Ben Ando reports.