For centuries, man has relied on its best friend for companionship, but for the Metropolitan Police, and London, dogs are an important part of the force.
Police sniffer dogs are now a common sight at public events, highly trained to find narcotics and also explosives.
One of those dogs is Paddy, who works with PC Ricky Beckford, to detect and track drugs, criminals, bombs, stolen property or people.
Search dogs must be very calm and methodical, but also be highly motivated.
Their training is reward based and they must bark or freeze when they have detected the explosives or narcotics.
In the video, Paddy sniffs out a scent before freezing when he finds what he is looking for.
He is rewarded with his favourite tennis ball.
PC Beckford said: "I have every faith in Paddy that he can do his job to the highest ability and together I believe we make a superb team and we will keep London safe."
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