MADRID (AP) — Spanish rescuers working against the clock to find a missing 2-year-old toddler say they have found hair of the boy in soil extracted from a narrow borehole that is 100 meters (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.

Adults can't enter the waterhole, whose diameter is narrower than 25 centimeters (10 inches). Authorities say the boy fell in the unmarked hole Sunday after walking away from his parents.