Sniffer dogs are being used to search an area of scrubland close to where Madeleine McCann went missing in Portugal seven years ago.

The development came as British officers, accompanied by their Portuguese counterparts, spent a second day investigating the hilly area in the resort of Praia da Luz on the Algarve.

Two sniffer dogs accompanied by British police spent around five minutes on a flat area of the scrubland, at the bottom of a slope.

They were then taken away out of sight, while around 10 officers stood around in discussion.

Specialist teams are thought to be using ground-penetrating radar equipment to probe the ground, looking for disturbed earth.

The large section of land is being guarded day and night by armed local police with dogs, and a large yellow-and-white cordon was put in place ahead of the search for clues about Madeleine, who disappeared in May 2007 aged three.

A number of small tents have been erected inside the cordon, thought to be where officers are concentrating their efforts.

The land, a few minutes' walk from the Ocean Club resort apartment where Madeleine was staying with her family, has been searched before.

The two spaniels were then brought out again and spent a few minutes in the long grass as their handlers looked on.

Around six Portuguese police vans could be seen on top of a large mound in the middle of the scrubland, which overlooks the sea.

The cordon was lowered down for two hired vans to drive in and they then reversed along a track before stopping near two blue tents.

TV crews and journalists from around the world were gathered at the cordon as the search - seen as one of the biggest developments in the investigation in recent years - takes place.