The ongoing investigation into the disappearance of Madeleine McCann could be abandoned as funding runs out.

The £12 million operation led by Scotland Yard is reportedly producing no new leads with detectives rarely visiting the Portuguese resort where Madeleine vanished in 2007. The investigation around her disappearance, named Operation Grange, was scaled back considerably in 2015. The Mail on Sunday reports that there have been no "earth-shattering leads" or major breakthroughs in the case for some time. Rather, four detectives working on the operation have been focusing on "grunt work" which involves locating known sex offenders in the area and ruling out their involvement in Maddie's disappearance. The detectives were granted £150,000 by the British government to continue working until the end of this month, but no further decision on funding has since been made. "Most of what Operation Grange is doing is having things set up to knock down and rule out, rather than pursuing a particular fantastic lead that could unlock it all," said a source. "I’m not aware of any earth-shattering lead or breakthrough imminently." This comes following a renewed interest in the Madeleine McCann case due to the recent Netflix docu-series about her disappearance. The then three-year-old vanished from her parent's Praia da Luz apartment while they were having dinner with their friends in a nearby restaurant. A spokesperson for the Metropolitan Police said that the investigation into the disappearance of Madeleine "remains ongoing." The UK Home Office has since confirmed it has received a request for more funding.