Nikhil was rushed to the primary health centre in Mauranipur where the doctors declared him dead, SP Dinesh Singh said.
The boy appeared to have died of drowning as water had come into the borewell, the SP added.
The boy was stuck at a depth of 50 feet. He was provided oxygen to enable him breathe.
The land around the borewell had been dug up to 35 feet to rescue him.
The child fell into the borewell when his family members were working in the fields.