ADELAIDE (Reuters) - England could hold the answer to one of Australia`s biggest "whodunnits" - a giant image of a naked Aboriginal man mysteriously carved into the outback. Australian officials on Tuesday found a dedication plaque at the remote site, tipped off by a statement faxed to journalists by an anonymous source who claimed to have created the figure. The four kilometre long figure was found etched last year into red soil near Marree, 700 kilometres north of Adelaide. Police have been unable to discover who was responsible. The site was closed off after local Aborigines declared the image a desecration of their spiritual land. The anonymous fax promised a trail of clues about the origins of the so-called Marree Man will be unearthed in coming weeks at the sites of giant chalk drawings in England. "The first answer was buried in a sealed container near the Cerne Giant, Dorset, England," the fax said. "It relates to the question `Who (is responsible)?`." The figure appears to depict an Aboriginal hunter holding a traditional throwing stick. It has a circumference of about 30 kilometres and outlines as wide as 32 metres which locals believe would have required heavy machinery, satellite tracking equipment and up to six weeks to complete. The inscription on the plaque buried near the figure`s nose read: "In honour of the land they once knew. His attainments in these pursuits are extraordinary; a constant source of wonderment and admiration". The fax said the exact location of the clue at the Cerne Giant, a 55 metre figure carved into chalk, would be given on January 24 to several unnamed Cerne residents. A second answer would be provided later near the Long Man of Wilmington, another English chalk carving.