Madrid -- Spanish rescuers working against the clock to find asay they have found hair of the boy in soil extracted from a narrow borehole that is 330 feet deep.
The discovery is giving them renewed confidence that the toddler could be at a deeper section than machinery and surveillance equipment has reached.
The government's representative in the Malaga province says DNA tests have given rescuers "scientific evidence that the minor is there."
Maria Gamez also said Wednesday that workers are aiming to dig a side tunnel to reach the shaft. She said rescuers failed to extract soil from the well on Tuesday with heavy suction machinery during overnight works.
Spanish daily El Pais reported Wednesday that rescuers were actually working on two new tunnels, one being bored into the hillside at an angle and another parallel to the one in which the boy is trapped. They were hoping to connect one of those new shafts to the borehole within 48 hours.
Adults can't enter the waterhole, the diameter of which is narrower than 10 inches. Authorities say the boy fell in the unmarked hole Sunday after walking away from his parents.
According to CBS News partner network BBC News, the same family lost another son some kind of accident less than two years ago. There had been no sign of life from the boy, named only as Julen, from the borehole as of Wednesday morning.
"I still have hope that my son is alive," Julen's father Jose Rosello was quoted as saying by El Pais. "We can't stop until we get my son out of there."