Efforts to reach a two-year-old boy who fell into a borehole in southern Spain on January 13 hit a major snag on Tuesday when engineers said they would have to widen a parallel shaft before they could dig a horizontal passage to reach the toddler.
Miners had been drilling day and night to create the shaft 60 metres (197 ft) deep, which they finished on Monday and started lining with thick metal pipes. Their hope was to be able to cut across by Tuesday to find the toddler, Julen.
"Technical difficulties have cropped up with the casing of the well after the depth of 40 metres," said a spokeswoman for the regional government at the site, adding that the thick metal pipes will be removed and drilling resumed.
"It is impossible to estimate how long it will take. The operation has already begun," she said.
Julen fell down the borehole shaft as his family walked through a private estate in Totalan, Malaga.
There have been no signs of life since.
Rescuers found that the borehole - 100 metres (300 feet) deep and just 25 cm (10 inches) wide - was blocked with earth, raising fears that soil had collapsed onto the child.
Engineers have said that digging the horizontal passage would be the most dangerous part of the effort. Spanish miners and engineers have been joined by workers from a Swedish firm who helped locate 33 Chilean miners rescued after 69 days underground more than seven years ago.
Children and families have been holding candlelight vigils across Spain in support of the missing boy.
El Pais reported that his parents suffered another tragedy in 2017 when their three-year-old son died suddenly after suffering a cardiac arrest while walking along a beach.
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