Soldiers and engineering experts in Vietnam are working to free a 10-year-old boy trapped in a buried hollow concrete pillar on a construction site.

Rescuers hope to raise the pillar from its 35-metre-deep hole and cut the boy out, but after days trapped inside it is not clear whether he is alive.

Thai Ly Hao Nam was reportedly searching for scrap iron with friends when he fell through the 25-centimetre-wide opening of the pillar at the construction site for a new bridge in the Mekong delta province of Dong Thap on Saturday. 

He was heard crying for help shortly after he fell into the pile on Saturday morning, but rescuers received no response from him on Monday as they lowered a camera down to try to locate his position in the 35-metre-deep support pillar.

A wider 19-metre metal pipe has been lowered around the concrete tube he is trapped in to allow them to remove mud from around the pillar and try to lift it out.

Rescuers were softening and removing mud and water to reduce pressure around the pillar before trying to lift it up.

About 100 soldiers have been deployed to the site, which has been sealed off from the public as the rescue effort continues. 

“The boy has been trapped inside the small pillar for four days, with assumption of multiple injuries,” deputy chairman of the Dong Thap provincial people’s committee Doan Tan Buu said. 

Efforts to lift the pile with cranes and excavators have failed. 

“We had tried our best to rescue the boy using on-the-spot measures and equipment,” Mr Buu told state-controlled Tuoi Tre newspaper.

“We later had to report and asked for help from national levels and people with expertise.” 

AFP/ Reuters