The dog trained to sniff out smuggled small boats

More than 1,600 miles (2,574km) from the white cliffs of Dover is one of the world's busiest land borders.

Customs staff use an English pointer called Adele to carry out checks at this gateway to the European Union, a location that is a frontline against people smugglers.

At the Kapitan Andreevo border control point in Bulgaria, on the border with Turkey, they are trying to disrupt the flow of small boats that are being transported to the beaches of northern France, often disguised as paddling pools or tarpaulins.

Adele, a UK-funded sniffer dog, has been trained to disrupt the smuggling by sniffing out the rubber the boats are made from.