The bodies were recovered during rescue operation that started on Friday morning, Jharkhand Director General of Police (DGP) D.K. Pandey told IANS.
The chances of survival of all trapped people were negligible, police sources said.
Heap of mud caved in at the entry point of Lalmatia mines of Eastern Coalfields Limited (ECL), the police said.
At the time of the cave-in at the Rajmahal Open Cast Mines of Paharia Bhorya site, more than 70 vehicles were inside.
Rescue operation could not begin due to night fog, the police said.
The National Disaster Response Force (NDRF) team reached around 11 a.m. from Patna.
The local police and administration were involved in the rescue operation.
The Director General of Mines Safety (DGMS) has sent a team to the spot to investigate.
According to a DGMS official, the safety measures were overlooked during mining.
The locals said there was a crack in the heap of mud which collapsed and blocked the entry point of the mine.
Mining operations were taking place about 200 feet beneath the ground.