Spanish officials confirmed on Wednesday that two-year-old Julen is trapped inside a groundwater prospecting well.
A representative of the central Socialist government in Andalusia, Maria Gamez, told reporters that emergency services found, inside the well, biological traces that belong to the child.
Jose Rosello, the father of the boy told reporters he is still confident his child will be found alive.
Spanish media said the two-year-old boy was seen falling into the 9.8 inch wide and around 328 feet deep well on Sunday when the family was taking a stroll through a private estate in Totalan, Malaga in the South of Spain.
Emergency services are using cameras to locate the child but pieces of soil blocking the way are complicating the access.
Spanish police confirmed that members of a Swedish firm which helped locate the 33 Chilean miners rescued after 69 days underground more than seven years ago, arrived on Tuesday to the site to help in the search for the boy.
Alternative routes are being studied.