Tonghua Mining (Group) Co in Jilin province concealed the exact death toll from a coal mine gas blast in March, according to an investigation report released by the State Council on Thursday.

The company also concealed deaths in other mine accidents, the report said.

Previous explosions in the mine had not been reported, according to the report. Thirty-six people were killed in the March accident, including a man who died in hospital, the report said.

The company, however, reported that only 28 people were killed and another 13 injured.

Zhao Xianwen, chairman and general manager of the company, and Wang Shengyu, executive deputy general manager of the company, decided to conceal the full extent of the casualties. They secretly contacted the family members of the unpublicized dead and paid them compensation. After contacting the victims' family, they falsified death certificates and cremated the bodies, according to the report.

Relevant departments immediately established a special task force to investigate after they received a tip-off in April. The State Administration of Work Safety also urged relevant departments in Jilin to thoroughly investigate the case after the administration received calls from a whistle-blower.

The investigation also found that Tonghua Mining (Group) Co had concealed six deaths in another five coal mine explosions in 2012. Three explosions had occurred in the mine before it was hit by the blast in March, but they were not reported as there were no injuries, the investigation discovered.