British police from Scotland Yard will return to Portugal next week to question seven suspects in the disappearance of Madeleine McCann.
Three of those facing questions have been questioned before.
Police officers will travel to Praia da Luz to hold meetings with senior Portuguese detectives about the girl who went missing more than seven years ago.
The McCanns have strong links to Donegal with relatives in the county. Madeleine visited her in April 2007, a few weeks before she disappeared.
Portugese police have granted permission to UK officers interview up to seven suspects – three of whom have already been questioned once before.
In June Scotland Yard detectives shadowed three searches of wasteland near the Ocean Club but no obvious clues were found.
Some materials gathered in the search were sent for forensic examination but officers were not hopeful of a breakthrough in the investigation.