"The majority of Neruda's friends were made prisoners or had to hide or seek political asylum in other countries, " it says.

CNN: Chilean Communists call for Neruda's exhumation

On days when the dogs are not involved in investigations, their handlers hide the scents or objects they are trained to seek to keep them sharp and to maintain the work-reward practice.

CNN: Canines patrol grounds daily

Criminal gangs use this equipment to hide their activity, for example blocking the GPS tracking systems in the lorries or high-performance cars they seek to steal.

BBC: UK 'over-reliant' on GPS signals, engineers warn