LONDON (AFP).- British postcards sent home by German boy scouts that were used by the Nazis when planning to invade the country, sold for £1,000 ($1,600, 1,350 euros) at auction in London on Wednesday.

The postcards were used to build up a geographical picture of Britain and form part of a rare set of eight booklets which were sold by the Dreweatts auction house.

The dossiers also include many maps and photographs, and were to be used by strategists planning "Operation Sealion", the 1940 mission to invade Britain.

The plan was eventually shelved when Adolf Hitler was told it would not succeed.

The booklets include analysis of soil types, possible landing beaches and maps highlighting local police and railway stations.

Among the postcards were many sent by unwitting boy scouts, who had visited the country on exchange programmes and jamborees.

They include black-and-white images showing the south-coast harbours of Plymouth, Folkestone, Porthleven and Newlyn.