It said the accident occurred at Akookoso, in the Amansie Central district, on Tuesday when they were in the pit digging for gold.
The child was with her parents in the pit.
Radio XYZ quoted ASP Prince Odoom, Commander of the Jacobu district, as saying seven others who were also digging for gold in the same area escaped after the accident.
The bodies have been recovered and taken to a nearby hospital.
Many people have been buried alive in pits as thousands of illegal miners continue to do for gold and diamonds.
In spite of the warnings by the government on the severe damage they are causing to the country’s environment and water bodies.