(NewsNation) — Authorities in Portugal confirmed Thursday that the search in the case of missing British girl Madeleine McCann has ended.

The latest efforts in the 16-year-old hunt wrapped up Thursday after police collected unspecified samples in the Arada Dam reservoir and surrounding areas in Portugal.

Police have not said whether any useful clues were found during the three-day search that involved sniffer dogs, use of a tractor-based tree-cutter and investigators raking the cleared ground in a few small areas.

Officials said the search “resulted in the collection of some material,” which will be analyzed. However, there was no indication that anything conclusive was found. The search was requested by German authorities.

McCann was 3 years old when she disappeared in 2007 from her family’s vacation apartment in the Algarve resort region of Portugal. She and her siblings, 2-year-old twins, were left asleep in the family’s apartment while their parents, Gerry and Kate McCann, ate with friends in a nearby restaurant.

In 2022, German prosecutors named Christian Brueckner an official suspect in McCann’s disappearance. The convicted child abuser and drug dealer is behind bars in Germany for raping a 72-year-old woman in the same part of the Algarve.

Brueckner has denied any involvement in the disappearance. No body has been found.