Hundreds of rescue workers are trying to retrieve the boy at the construction site in Dong Thap province where he is said to have walked around looking for metal.
Called for help
It was two days ago that the boy fell into the 25 centimeter wide concrete pipe.
- We try our best.
We cannot determine the boy's condition yet, a rescue worker told the AFP news agency.
The boy was heard calling for help two days ago, but has now reportedly stopped communicating with those on the ground.
At the same time, oxygen has been continuously pumped into the hole, writes the Vietnamese newspaper Tuoi Tre.
Open up the ground
On Monday, Vietnamese Prime Minister Pham Minh Chinh asked rescue workers at the federal level to join the local rescue force.
Several different methods have been tried to get the boy up.
Most recently, they have tried to drill and loosen the surrounding ground to be able to pull up the concrete pipe.