Portuguese police investigating the disappearance of Madeleine McCann have questioned the estranged husband of suspect Robert Murat’s girlfriend for a second time, it has been claimed.

Luis Antonio is the estranged husband of Robert Murat's girlfriend Michaela Walczuch
Mr Antonio, 37, who worked as a pool cleaner at the Ocean Club resort where Madeleine disappeared last May, was one of five people questioned with links to the complex, according to newspaper 24 Horas.

A source told the newspaper: "Several police interviews have been repeated and the statements are being analysed to try to find any lead that could result in a new line of investigation."

Mr Antonio and Miss Walczuch were initially interviewed after Murat, 34, was made an official suspect, or arguido, two weeks after the little girl vanished, but have always been considered witnesses.

Murat, who lives with his mother less than 150 yards from the resort where the McCanns were staying, has always denied any involvement in the case.

Earlier this week, justice minister Alberto Costa told a parliamentary committee in Lisbon that police were approaching the “conclusion�?of the investigation.

But 24 Horas claimed the investigating judge presiding over the case, Judge Pedro Frias, was considering a request to extend the secrecy surrounding the files by another 90 days.

He is understood to have guaranteed one extension already, dashing Kate and Gerry McCann’s hopes of clearing their names in connection with their daughter’s disappearance.

The couple were both made arguidos in September last year but have pledged to carry on searching for Madeleine “until she is found�?

A police source said it was unlikely that the case would ever be completely closed: “An investigation of this nature always remains open. All the leads that arise are appropriately investigated.�?/DIV>