A timeline of some of the key events since Madeleine McCann disappeared in 2007 following reports suspects have been identified.
The parents of Madeleine McCann have admitted it was "difficult" to allow their twins to enjoy the same freedom as other children.
Our correspondent Gareth Owen has revisited Praia da Luz, five years since the disappearance of Madeleine McCann.
The mother of missing Madeleine McCann from Rothley in Leicestershire has vowed never to give up looking for her missing daughter.
– Kate McCann, April 2013
The search goes on, in a major way."
The Met Police are currently reviewing the case of Madeleine's disappearance and are liaising with police in Portugal where she went missing six years ago today.
Kate and Gerry McCann says Madeleine's birthday is more difficult than the anniversary of her disappearance.
Madeleine would be celebrating her tenth birthday on the 12th May 2013.
The couple admitted they still celebrate her birthday with a birthday tea and cake.
The parents of missing Leicestershire girl, Madeleine McCann, will mark the sixth anniversary of her disappearance with a small service in their village today.
Kate and Gerry McCann will attend an ceremony this evening in the centre of Rothley where they will say prayers and read poems.
It is six years to the day that Madeleine went missing in Praia da Luz in Portugal's Algarve on May 3rd 2007.
Madeleine would now be ten years old.
Madeleine McCann's parents have told ITV they won't give up hope that their daughter will be found, as they prepare to mark the sixth anniversary of her disappearance.
Kate and Gerry McCann from Rothley in Leicestershire, said the hunt for their daughter is escalating rather than winding down, following the involvement of the Metropolitan Police. Kate Fisher reports.
The parents of missing Madeleine McCann said this morning that it's hard letting go of their twins as they grow up.
The parents of Madeleine McCann still believe that there is a chance their daughter is still out there six years on from her disappearance.
The parents of the missing schoolgirl Madeleine McCann say it was initially hard to see children their daughter's age grow up.
A network designed to help track down abducted children within hours of them going missing has gone into operation.
Called Amber Alert Europe it is designed to alert a wide range of authorities across the EU simultaneously when a child is reported missing.
The technology means police, press and the public can be instantly alerted to a missing child, through tools like road signs, TV, radio, social media, computer pop-ups, and text messages.
People should register on the website.
The mother of missing Madeleine McCann, has announced that she'll be running the Virgin London Marathon 2013 in aid of the Missing People charity.
Madeleine went missing in May 2007 while on holiday with her parents in Praia da Luz.
On her Just Giving page, Kate McCann said:
"If I’m honest, I would happily have gone through my life without ever contemplating running a marathon, or even a half-marathon for that matter!
"However, knowing what it’s like to be living with a child missing and believing very strongly in what the workers at the charity do in helping other families like mine, I realised it was a challenge that I had to take."
Kate and Jerry McCann live in Rothley, Leicestershire.