Madeline went missing from her bed at the now-infamous address of apartment 5A on Rua Dr Agostinho da Silva as her parents, Gerry and Kate, dined with friends at a restaurant nearby. It’s been 10 years since the little girl seemed to vanish into thin air—and no trace of her has been found since.

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The mystery of Madeline’s disappearance has made headlines around the world over the years, and police and other experts have followed countless leads. 

Some believe that she was murdered by accident as the result of a burglary gone wrong; others accused her distraught parents of being involved in her disappearance. Detectives pursued other tips as well: Had she been abducted and killed by a local pedophile? Kidnapped by a European sex-trafficking gang? Snatched by a childless couple desperate for one of their own? 

Twelve days after Maddie’s disappearance, 34-year-old British-Portuguese property consultant Robert Murat was named as the first “arguido,” or person of interest, in the case. After searching his home and other locations, investigators concluded that Murat had no link to Madeline’s disappearance, and his arguido status was removed in July 2008.

The first senior detective on the case, Gonçalo Amaral, believed Madeleine died in the family’s rented holiday apartment, and her parents covered up her death and disposed of her body. This would be the beginning of an often contentious relationship between the McCanns—who have always denied any role in their daughter’s disappearance—and the Portuguese police. 

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According to media reports in 2007, British sniffer dogs trained to detect body scent and blood reacted in the vacation apartment. There were also reports that DNA potentially matching Madeleine's had been found in a car that Gerry and Kate McCann rented 25 days after Madeline disappeared.

The media overreported the significance of this DNA match at the time, saying it was confirmed to be Madeleine's. In reality, the process used to match the DNA was, even in the case of full matches, not a perfect one. And in this particular case, only 15 of the 19 matches were confirmed.

The misinterpretation by Portuguese investigators of this forensic evidence led to the McCanns being questioned and seen as official suspects. When they were questioned over the DNA discoveries, Kate was asked 48 questions over an 11-hour interrogation, but instead of answering them she used her right to remain silent, speaking only once. 

Some of the questions she was asked were: “Did you manage to sleep? Did Maddie suffer from any illness or take any medication? Did you work every day?” Kate’s refusal to answer seemingly innocuous queries led police to accuse her of negatively affecting the search for Maddie.

The couple were finally ruled out when the Portuguese case was closed, unsolved, after 15 months.

Gerry and Kate continue to and have always denied any role in their daughter’s disappearance, and two Portuguese investigations and a Scotland Yard inquiry have found no evidence to suggest that the parents were involved.

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After hearing a report that Madeleine had been photographed by a stranger on the beach before her disappearance, another theory investigated by Portuguese police was that she could have been stolen by human traffickers. Human-trafficking gangs are known to operate in the northwest African country of Mauritania, which became the last country in the world to abolish slavery, in 1981.

This theory appeared to be bolstered when several witnesses reported possible sightings of Madeleine in Morocco. A private investigator hired by the McCanns visited Morocco, but could find no evidence that she had been there.

In 2011, Portuguese detectives reopened their investigation after studying a series of attacks in resorts along the Algarve coast in the years up to 2007 in which a man entered apartments of British vacationers and molested young girls while they slept. The investigators’ main suspect, Ocean Club waiter Euclides Monteiro was ruled out by DNA evidence. The perpetrator of these attacks also remains at large.

Convicted British pedophile Raymond Hewlett was also reportedly considered as a potential suspect. He had been staying in a converted truck at a camping site near the Ocean Club resort in Praia da Luz in 2007. He died of cancer in Germany in 2010.

Another theory is that Madeleine left the apartment to look for her parents, and then had some sort of accident—perhaps falling into a pit at a construction site, or was struck by a motorist who then panicked and hid the body. However, Madeleine would have had to make it through a number of obstacles unusual for a three-year-old.

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Detectives recently revealed they are working on an additional theory that the youngster was kidnapped by a European trafficking gang. According to this theory, the “spotters” are believed to have targeted the charismatic blonde toddler and taken photographs of her while she was playing on the beach and beside the pool at her holiday apartment. 

In an interview marking the 10th anniversary of Maddie’s disappearance, Gerry and Kate spoke of their enduring hope that they will find out what happened to their daughter someday. They recently suffered a setback when they lost their eight-year libel battle against former police chief Gonçalo Amaral who published a book accusing them of covering up their daughter’s death. He claimed in the book The Truth Of The Lie that Madeleine had died in their holiday flat and they had faked her abduction to cover up the tragedy. 

Amaral was also involved in the investigation of a disappearance of another little girl, Joana Cipriano, only seven miles away from the McCanns' holiday destination, about two years before Madeleine's disappearance. In 2009, Amaral was convicted of perjury after concealing the fact that other officers beat the little girl's mother until she confessed to her murder. 

Scotland Yard shut down its investigation in 2016, but Madeleine’s family has vowed to continue to search for answers. 

Read more: Manchester Evening News; Sky News; DailyMail; The Mirror; FindMadeleine.com

This Story Was First Published on Crime Feed.   

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Featured photo of Madeleine McCann at age three, next to an age-progressed depiction of how she may have looked at age nine via Wikipedia; Additional photos via Find Madeleine