Detectives investigating the disappearance of Madeleine McCann have ruled out a key sighting on the day she vanished and are trying to identify a number of mysterious men seen lurking around the apartment where it is believed she was abducted.
Officers from Scotland Yard now say that a man seen carrying a child by the McCanns' friend Jane Tanner was an innocent British holiday maker, and are instead focusing on another man with dark hair who was also seen with a little girl in his arms around 45 minutes later.
Investigators are looking at a spate of break-ins in the area, one of which happened in the same week a year before Madeleine went missing, where a man got into a flat where young children were sleeping.
She vanished on May 3 2007 from a holiday apartment in Praia de Luz, Portugal, as her parents dined at a nearby tapas restaurant with friends.
Speaking after a new appeal aired on BBC Crimewatch, Detective Chief Inspector Andy Redwood said: "Our focus in terms of understanding what happened on the night of May 3 has now given us a shift of emphasis. We are almost certain that the man seen by Jane Tanner is not Madeleine's abductor.
"It takes us through to a position at 10pm when we see another man who is walking towards the ocean, close by to the apartment, with a young child in his arms. This child is described as being about three to four years of age with blonde hair, possibly wearing pyjamas, and the man is a white man with dark hair.
"If this is you, and you are nothing to do with Madeleine's disappearance, then we really need to speak to you. It's so important for us to eliminate innocent sightings. But equally if anybody is looking at those e-fits and recognises the person, for whatever reason, then please have the courage to call in and tell us."
Investigators are also trying to identify fair-haired men seen near the apartment at the time who could be Dutch or German, and TV appeals will be run in Holland and Germany, although not Portugal.
Mr Redwood said: "There are one or two men who appear to be lurking around the apartments in the area itself. A consistent theme in the physical descriptions of those sightings is possibly blond or fair hair. So we are just asking the public quite simply, are these connected? But more importantly is this you? Because if it's innocent, then it's really important for us to take out those innocent sightings."
They are also looking at bogus charity collectors who were operating in the area at the time, and at a spate of burglaries that peaked in the month Madeleine went missing.
Mr Redwood added: "Whilst the numbers are low, we can see that there was an increase in burglary in Praia de Luz between January and April 2007 that spiked in April 2007. Windows were a feature, as well as burglaries taking place in the evening.
"We can see that in the week that Madeleine disappeared but in the year before in 2006, that two children were in an apartment when a man came in and he appears to have come through the patio door, had a look around inside and definitely had a look into one of the cots and then left without taking anything. Then one of the children raised the alarm.
"We're particularly interested in that event as to whether it has any resonance to the disappearance of Madeleine. The man was described as being a white man with dark hair."
On the day that Madeleine disappeared, there were four occasions where bogus charity collectors targeted properties in the area.
In the Crimewatch appeal, Mr Redwood said that Madeleine's disappearance could have been a planned abduction.
"Madeleine McCann's disappearance does, on one reading of the evidence, have the hallmarks of a pre-planned abduction that would undoubtedly have involved reconnaissance," he said.
Investigators are using a number of e-fits, two of which are of the man who was seen carrying a child.
The others are drawn from descriptions of men who were seen in the area around the time that Madeleine disappeared. Two are of fair-haired men who fit similar descriptions.
One is of a man who was seen twice by the same witness near the flat where the McCanns were staying. He was 30 to 35, thin, with short hair, shaving spots on his face and was wearing a black leather jacket. Another witness saw a similar-looking man in the resort.
There are also two e-fits of Portuguese men - one aged 40 to 45, who knocked on the door of the apartment where the McCanns were to stay on April 25 or 26 between 2.30pm and 3pm, saying that he was a charity collector.
The other, aged 25 to 30, approached a property on the Rua do Ramalhete, near the Ocean Club, at around 4pm on May 3.
There is a £20,000 reward for information leading to the arrest and prosecution of those responsible for Madeleine's disappearance.