Among the four suspects are three managers, the emergency rescue headquarters said in a statement.
The workers were trapped after an explosion on Tuesday at the private coal mine in Qitaihe City, Heilongjiang province.
Of the 22 miners trapped, 21 were confirmed dead and one remained missing. Rescuers retrieved the 21 bodies last night and search operation for the missing miner is on.
State-run CCTV reported the workers could not be reached by rescuers due to presence of poisonous gases even as insurance firms began contacting the families of the workers to settle claims.
Initial enquiries showed that the blast was an accident and the mine was unlicensed, police said.
PTI