The Drapers told Fox News they thought the yelling was children playing in the backyard when they walked inside at approximately 7:30pm.

But when they found their grandkids were not making the noise, they listened closer and heard cries for help. 

The couple called West Valley City police. A wall had to be ripped out of the home to let the boy out.

Mr Draper told the station: 'Through a noble effort of about an hour of cutting our house up...they were able to retrieve the child and overall everything was successful.'

Incredibly, he was unharmed.

'He was black, just covered in soot but actually looked pretty well,' Mr Draper recalled. 

Police said the boy's mother had reported him missing earlier in the day after he left the family home and failed to return.

Mr Draper said: 'They asked him why he had gone down the chimney and he said he was looking for food and water so evidently he was wandering the neighbourhood.'

The boy's family had yet to issue comment at press time.