This is the second accident involving Singareni Collieries in four months. Eighteen miners drowned when a wall collapsed and part of a mine was flooded on June 16.
The latest accident occurred when workers reportedly triggered a blast inside the 15-year-old mine to break through to a new area for mining.
Workers blamed the accident on the carelessness of mine authorities, saying no precautions were taken before blasts were carried out.
"This is a 15-year-old mine and such mines are prone to these sort of accidents. But the management was careless,'' said Y. Gattaiah, a mine workers union leader in Godavarikhani.
Chandrababu Naidu, the state's top elected official ordered a probe by a high court judge into the cause of the accident and announced a payment of rupees 600,000 (US$13,185) to the families of each of the victims.
Police and miners retrieved four bodies and efforts continued to find the bodies of the others.
Karimnagar is 300 kilometers north of the state capital, Hyderabad.
