Stray dogs in Hong Kong are getting a second life as Police Sniffer dogs to locate drugs and be part of the Hong Kong Police Force.

In the last three years, Barry, a homeless dog was on 150 detection missions.

These dogs work closely with the police and can do the work that machines cannot do and they can do it faster.A sniffer dog routinely checks vehicles, containers, and people and they are often used in airports and other ports of entry.

These dogs know what they are doing and they are sometimes released by handlers so they can carry out difficult functions independently.

When a trained stray dog barks at a bag or something that spurs a response, the dog has done its job. Then another police officer investigates content in the bag. The sniffer dog is rewarded when his task is finished. Once trained, police dogs are given a leash and sometimes a bullet proof vest.

Stray dogs have a great sense of smell since they are usually scrounging around for food. They are also great companion dogs because they rarely attack people. This makes them amenable for working in police sniffer units.