A bunch of nosy sniffer dogs helped discover more than £8,500 of suspected illegal and untaxed tobacco in Mitcham this week.

A raid on two convenience stores allowed Yoyo, a specially trained spaniel, to find thousands of cigarettes and rolling tobacco stashed above a false ceiling and inside a cash register.

Carried out by trading standards officers from Merton Council, the raids were part of an awareness raising campaign that highlights the more than £100m profits criminal gangs make in selling illegal tobacco each year.

Councillor Ross Garrod, cabinet member for street cleanliness and parking, said: “The products are unregulated, untaxed and often sold under-the-counter.

“This means that they are available at far reduced prices, making it easier for children to buy them and start smoking at a young age.

“We all know how dangerous cigarettes are for your health but their illegal counterparts can be even worse with a well publicised by the Local Government Association last year finding everything for excrement, mould and dead flies in them.”

Telling signs of illegal tobacco include packets with no pictures of health warnings, foreign language with health warnings and being sold in unusual locations such as pubs and private houses.

Previously, Yoyo was able to bring in a half-a-million pound haul of cigarettes elsewhere in the capital, assisted that day by Phoebe, Ralph and Arthur.