Ben Needham search resumes on Kos Greek and British police dig up a field in the search for Ben Needham on the island of Kos. The search for Ben Needham resumed in earnest on Friday as British police equipped with sonar equipment started excavating the site on the Aegean island of Kos where the toddler went missing 21 years ago. More than 40 officers and search and rescue volunteers participated in the painstaking process of digging up the area around an old farmhouse where the Sheffield boy disappeared. Among the team were 16 search advisers drafted from units across the UK, and cadaver dogs trained in tracking human remains. Stergios Sentouras, the highest ranking police official in the Northern Dodecannese, the chain of islands to which Kos belongs, said: "Technology has advanced so dramatically, the investigation will be like no other conducted so far. The investigation will be very, very methodical. We want to help in whatever way we can. South Yorkshire police, who are leading the investigation on the ground, said the team would use scanning, sonar and ground penetration devices, focusing on a mound of rubble where the toddler may accidentally have been buried. The land lies within sight of the farmhouse that the boy's grandfather was renovating at the time of the disappearance. "There are a number of scenarios but what we are looking at now is the possibility that rather than being snatched, something - an accident or otherwise - happened on the ground where a lot of construction work was in process at the time," a South Yorkshire police spokesman said. There are two possibilities. Either we find something or we don't, and if we don't that eliminates one line of inquiry. In the event that human remains were found, a lengthy process of identification through DNA analysis would follow. Ben's mother, Kerry, flew to Kos with police family liaison officers. In a statement released by Sheffield police, she said: "I am so pleased that the investigation is now moving forward and that the Greek authorities are showing a true commitment to investigate Ben's disappearance." The case has never received the attention given to that of Madeleine McCann, but more than 200 possible sightings of Ben have been reported over the years and Mrs Needham has followed up each one. Ioannis Ioannidis, who runs the Kos Tribune, said the toddler's disappearance had cast "a long shadow over our island." "It is a mystery that everyone wants to solve," he said. Everyone, I know, has at some point asked what happened to that boy? We have to resolve this once and for all.