Witnesses saw these men on a path looking towards the McCann’s apartment, in the stairwell of the block, and in an empty apartment two doors down from where the family were staying.
Mr Redwood, who suggested it bore the hallmarks of a pre-planned abduction involving reconnaissance, said: “A consistent theme in the physical descriptions of those sightings is possibly blond or fair hair.”
Officers 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: “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.
“The man was described as being a white man with dark hair.”