The disappearance of Madeleine McCann more than four years ago sparked an international outpouring of grief. AP FILE PHOTO

Recent visits to Spain by Scotland Yard detectives are sparking fresh speculation about the 2007 disappearance of Madeleine McCann.

Detectives have been flying to Spain over the past two weeks to investigate new developments in the case of the British 3-year-old who disappeared from a vacation apartment in Portugal as her parents ate at a tapas bar 100 metres away.

The detectives won’t say why they spent three days visiting police in Barcelona, but there are reports Madeleine was abducted in Portugal and smuggled across the border to Spain.

Though the official case was closed in 2008, Scotland Yard was directed to review the McCann files in May after Madeleine’s parents, Kate and Gerry McCann, both doctors, made an appeal to British Prime Minister David Cameron.

“There has been very good co-operation with Portuguese authorities and liaison will continue,” said a Scotland Yard spokesman.

“We are pleased that the review is making progress,” the couple said in a statement issued Monday.

While the initial reaction to their daughter’s disappearance was supportive — the outpouring of grief was compared to Princess Diana’s death, and celebrities such as J.K. Rowling and Richard Branson offered million-dollar rewards for her return — the mood shifted in the following months, as theories published by tabloids accused the McCanns of murdering Madeleine and covering up their crime.

Probably the most potent rumour was that the McCanns killed Madeleine, stored her body in a freezer, then used a rental car to dispose of it.

Headlines like “Corpse in McCann Car” and “Maddy DNA Bombshell: New Results Put Parents Back in the Spotlight” were ubiquitous.

Like Lindy Chamberlain — the Australian woman who testified a dingo stole her baby — before her and Casey Anthony since, Kate McCann was seen as aloof and criticized for not displaying appropriate emotional distress.

Last month, the McCanns told the an inquiry into the conduct of the British media that the tabloid headlines were “nothing short of disgusting.”

The McCanns successfully sued The Express, a British tabloid, for libel in March 2008.

That July, Portugal’s public prosecutor closed the investigation, concluding there was no evidence against the parents.

Still, theories abound. In February, Marcelino Italiano, an amateur sleuth, told the British Sun tabloid that Madeleine had been abducted by a pedophile ring based in the Algarve region of Portugal where the McCanns were staying.

“I know these people were involved,” said Italiano, an Angola-born nightclub bouncer. “I have been told that Madeleine may now be in America.”