Scotland Yard hunt six British cleaners driving a white van in search for missing Maddie British cleaners and Portuguese manual workers are among new suspects Many suspects worked at the complex where the three-year-old was staying Scotland Yard have conducted a review of the Portuguese inquiry Sources said "low-level" workers have become the focus of interest. By Ian Gallagher And Russell Myers British cleaners and Portuguese manual workers are among new suspects in the Madeleine McCann investigation, The Mail on Sunday has learned. Scotland Yard identified what they describe as "people of interest" during a review of the Portuguese inquiry into the three-year-old's disappearance in May, 2007. The suspects are thought to number 12 - not 20 as has been reported - and include a number of British cleaners who were working near the apartment complex where Madeleine, twin siblings Sean and Amelie and parents Gerry and Kate were staying. Scotland Yard identified what they say are 'people of interest' in the kidnap of Madeleine McCann Sources said "low-level" workers - handymen, cleaners and gardeners - have become the focus of interest. Some are thought to have been employed by the Ocean Club complex on a casual basis and may have already been interviewed. Police are said to be keen to trace six British cleaners who were working in Praia da Luz when Madeleine vanished and who didn't appear in the Portuguese files. They are said to have used a white van and went from apartment to apartment offering their services, chiefly concentrating on expats. Gerry McCann and Kate McCann take their twins Sean and Amelie to the creche at the Ocean Club Resort in 2007 The Ocean Club in Praia da Luz where Maddie was disappeared. Portuguese police refuse to reopen the case A source said: "There is quite a culture of people drifting from door to door offering services from everything from your garden to your roof or windows." As well as the manual workers there are a number of more obvious suspects who already appear in the Portuguese files but who British police feel haven't been "bottomed out" properly and therefore warrant further investigation. "There are a lot of people who could be explored further, if only to be eliminated," said Detective Chief Superintendent Hamish Campbell, head of Scotland Yard's Homicide and Serious Crime Command. However officers face having to break down Portuguese resistance to re-opening the inquiry. Officials in Lisbon say they can reopen the case only if there is new evidence. But it has been claimed that the new leads could, if properly explored, result in new evidence and possibly solve the Madeleine mystery. Madeleine disappeared in 2007 when she was on holiday with her parents and brother and sister in Portugal Kate and Gerry McCann have never given up hunting for their daughter Detectives examining the Portuguese files were alarmed that the original inquiry had not traced and interviewed all the staff and holidaymakers who were at the Ocean Club when Madeleine went missing. Last year the Met said that it had identified 195 fresh leads that should have been investigated either by conducting further witness interviews, eliminating suspects or carrying out forensic tests that were missing from the 2007 inquiry. Officers found unexplained gaps in the investigation timeline and that there had been a complete lack of forensic examination of mobile phone activity in the area on the night Madeleine disappeared. Madeleine in an Everton football shirt before she disappeared. British officers face difficulty in breaking down resistance in Portugal to reopening the case Madeleine McCann is seen how she may look as her ninth birthday approached in this computer-generated handout photograph released in 2012