(LONDON) -- Investigators still searching for Madeleine McCann, the British toddler who went missing from a Portuguese holiday rental home five years ago this week, say they believe the girl is still alive and they now have the "best opportunity" yet to solve the case.
McCann was 3-years-old when she vanished on vacation with her parents Kate and Gerry McCann and twin siblings in the Algarve region of Portugal. The girl's parents say they found Madeleine missing after having left the children in the home unsupervised while having dinner less than 500 feet away.
"[We are] seeking to bring closure to the case," Detective Chief Inspector Andy Redwood told the BBC.
Detectives for the first time since the investigation into McCann's disappearance, dubbed Operation Grange by U.K. police, say that as a result of evidence uncovered during their latest review they now believe there is a possibility Madeleine is still alive and are appealing for direct information concerning her whereabouts.
Police didn't specify what clues led them to believe the girl may still be still alive.
"I am satisfied that the systems and processes that we are bringing to this set of circumstances will give us the best opportunity to find those investigative opportunities that we can then present to our colleagues in Portugal," Redwood said.
Investigators released an age progression image of McCann on Wednesday as her ninth birthday approaches on May 12. The image was created in close collaboration with the family, according to a statement from the U.K.'s Metropolitan police.
British police on Wednesday called on Portugal to reopen the case, saying they have close to 200 leads that could help find the missing girl alive. But in Portugal there is much less support for reopening the investigation, and the McCann's own Portuguese lawyer says it is hard to find people who sympathize with the couple.
"Everyone believes I am defending a father and mother that killed the daughter and got rid of the corpse," the McCann's Portuguese lawyer Isabel Duarte said.
With 28 detectives and seven civilian support staff, the Operation Grange team is handling the massive trove of reports and documents on the case. Hundreds of reported sightings of Madeleine have come in since she disappeared, but they have all led nowhere.
After her reported disappearance on May 3, 2007, the Polícia Judiciária, the Portuguese investigative police, initially decided that the girl had been abducted, but soon stated that they hypothesized that she died in the rented house.
An Algarve resident named Robert Murat was named a suspect on May 17, 2007. In September of 2007, Kate and Gerry McCann were also named as suspects in the mystery surrounding what happened to their daughter, but they were cleared, along with Murat, in July of 2008.
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