The explosion occurred Wednesday at the privately run Liuguantun Colliery in Tangshan, a city in Hebei province, when 188 miners were underground, said the official Xinhua News Agency.
Xinhua said an earlier report that said 186 miners were underground was incorrect.
Eighty-two managed escaped on their own and 32 miners were immediately rescued but three of those later died, Xinhua said. The bodies of 71 miners had been recovered from the mine by early Thursday, bringing the death toll to 74, it said.
Xinhua reported that an additional 32 miners remained missing but did not explain why these miners were not included in the figure for the total underground when the blast occurred.
Rescuers searching for miners in an unrelated blast in northern China last week struggled unsuccessfully for days to get an accurate count of how many miners were working when that blast occurred, underscoring the mismanagement and inattention to safety protocols that plague the industry.
Li Yizhong, director of the State Administration of Work Safety, and Zhao Tiechui, director of the State Administration of Coal Mine Safety, departed Beijing for the site late Wednesday, the official Xinhua News Agency said.
Last year, more than 6,000 miners were killed in fires, floods, cave-ins and explosions, making China's shafts the world's deadliest. Corruption, lax safety rules and poor equipment are among factors often blamed for the accidents.
The government has shut down thousands of unsafe mines and punished mine owners who put profits ahead of lives. But China's enormous need for energy, stemming from its booming economy, has complicated the issue.
Mine accidents are reported on a near-daily basis, some involving huge death tolls. The worst in recent years occurred in February in northeastern Liaoning province, when an explosion killed 214 miners.
On Tuesday, rescuers recovered the body of the last miner missing in ain China's northeastern Heilongjiang province, bringing the number of fatalities in that blast to 171.
The accident prompted Premier Wen Jiabao to declare over the weekend that the industry was "chaotic and without safety enforcement in place," according to Li Yizhong, the director of China's State Administration of Work Safety.
Rescuers at the Sigou Coal Mine in central Henan province were on Wednesday still trying to save 42 miners trapped underground after the shaft flooded last Friday, Xinhua said.
Divers have been dispatched for the search, and rescuers have also fed a microphone into the mine to listen for signs of life, Xinhua said. So far, there has been no indication that the workers survived. A total of 76 miners were working underground at the time, and 34 escaped.
Authorities have detained 10 of the mine's officials, including the owner, who had fled but was captured after a "massive manhunt," Xinhua said.
As part of the crackdown, punishments are often meted out to local mine or government officials, many who try to escape the scene.