British ex-pat Robert Murat is being questioned as a witness by police as part of the investigation into the 2007 disappearance of Madeleine McCann.
It is understood Murat and his wife will both be questioned in connection with the case.
British police have travelled to the Algarve in Portugal where they have been sitting in on interviews conducted by Portuguese officers.
British ex-pat Robert Murat and his wife Michaela Walczuch have arrived at a police station in the Algarve to be questioned by police investigating the Madeleine McCann case.
British detectives are sitting in on interviews as Portuguese officers talk to 11 different witnesses.
Ms Walczuch's former husband Luis Antonio is also among those being questioned.
The identities of six of the 11 potential witnesses being interviewed in Portugal over missing Madeleine McCann have yet to be made public.
Those we do know include Robert Murat, a Brit who was the first person to be declared a suspect but was never arrested or charged, his wife Michaela Walczuch and her ex-husband Luis Antonio.
Joaquim Marques was today interviewed for the third time while British police sat in.
While Mario Marreiros, who worked at the Ocean Club hotel where Madeleine's family were staying, claims he saw a man acting suspiciously.
ITV News reporter Rebecca Barry has this report:
After three years heading the investigation, DCI Andy Redwood is stepping aside - his replacement may bring a fresh focus to the case.Read the full story ›
DCI Andy Redwood, the outgoing head of the Madeleine McCann investigation, has arrived at a Portuguese police station to begin taking part in the questioning of 11 witnesses.
ITV News reporter Rebecca Barry is in Praia da Luz.
DCI Andy Redwood has just arrived at police station in Faro to begin questioning of 11 people in connection with Madeleine #McCann
Detectives investigating the disappearance of Madeleine McCann are expected to begin questioning 11 people today.
British police working on the case are believed to have arrived in the Algarve to take part in interviews alongside Portuguese officers.
They will spend three days working on the case alongside their Portuguese counterparts, according to reports.
ITV News' Rebecca Barry, who is in Praia da Luz, says those set to be questioned "include British and Portuguese men and women, including some former members of staff from the Ocean Club, where the McCanns were staying when Madeleine went missing".
The British police delegation is thought to include DCI Nicola Wall, who has taken over the investigation into Madeleine's disappearance from DCI Andy Redwood, who is retiring.
Some 11 people "will be interviewed as witnesses" by the police searching for missing Madeleine McCann, Good Morning Britain heard.
British and Portuguese "men and women" are expected to be quizzed by the police over what happened to the missing youngster.
British police are expected to arrive in Portugal today to question a number of people over the disappearance of Madeleine McCann.
The three-year-old, from Rothley in Leicestershire, went missing from a holiday apartment in Praia da Luz in Portugal in 2007.
Scotland Yard detectives will be expected to interview Robert Murat, who was arrested as part of the Portuguese police investigation into her disappearance at the time.
As well as questioning seven suspects, four other people will be interviewed as potential witnesses.
British police travelled to Portugal over the summer and spent eight days searching three areas of Praia da Luz, but found no new evidence.
British detectives want Portuguese police to apply new techniques to items found in the McCann family apartment in a bid for a breakthrough.Read the full story ›