Police to quiz Madeleine's mother
Portuguese police are to re-interview the mother of missing Madeleine McCann.
Kate McCann and her husband Gerry have previously been interviewed over the disappearance of their daughter from an apartment in Praia da Luz on 3 May.
Mrs McCann will be accompanied by a lawyer for formal questioning as a witness. Police have previously said the McCanns are not suspects.
Separately, Portuguese detectives confirmed they had the partial results of forensic tests by a UK laboratory.
Mrs McCann, from Rothley in Leicestershire, is expected to arrive at Portimao police station in the Algarve at 1400 BST (1300 GMT).
The BBC's Steve Kingstone, in Portimao, said: "It's our understanding that what will take place here will be a formal police interview.
"This is not an informal meeting of the type the McCanns have had regularly with detectives since Madeleine disappeared."
He added that a family spokeswoman had stressed Kate McCann will be questioned as a witness not as a suspect.
Mr McCann is thought to face further questioning himself on Friday.
Portuguese police spokesman Chief Inspector Olegario Sousa said partial results from tests had been received but would give no further details.
Samples, including suspected traces of blood, were recovered from the McCann's holiday apartment.
The UK's Forensic Science Service has spent the past month analysing samples.