Ben Needham was just 21-months-old when he disappeared while on holiday with family in Kos.
Police now fear that the toddler could have been killed whilst on the Greek island, near where his grandparents were renovating a farmhouse.
A witness came forward earlier this year, claiming a digger driver who was working in the area may have been responsible for Ben’s death.
Earlier this week, police revealed they had found items of ‘slight interest’ since starting their search in the area near the farmhouse.
Pieces of fabric were found which are being analysed by forensics, in addition to a photo taken shortly after the boy’s disappearance which shows a newly planted tree.
Detective Inspector Jon Cousins said: “It was taken around 10 to 14 days after his disappearance.
“It is the earliest record we have and the closest record of the time Ben disappeared. There is an indication that a tree that is here now clearly wasn’t there at the time.
“We have been able to analyse that area with the experts who are here now and, of course, we are able to look at all the fauna and tree growth around it.”
And now investigators are closely examining an area in the olive grove behind the farmhouse, having found evidence of “decomposition”.
Soil samples were sent to the UK and are still being examined at a laboratory in Aberdeen.
Forensic scientists have yet to rule out whether the ‘decomposition’ is human or not.
Three other areas have also been tested but have been established as remains of a dog, bat, and human waste from a cess tank.
DI Cousins has said: "There is another area of decomposition that has not been ruled out yet and that is what we are working on.
"The scientists have been unable to determine what it is."
We will bring you more on this story as it happens.
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