The bulk of the casualties came when a gas explosion ripped through a mine in China's northwest Xinjiang region, killing at least 59 and leaving 24 unaccounted for, Xinhua new agency said.
A total of 87 people were working in the Shenlong Coal Mine, in Xinjiang's Fukang city, when the blast hit the shaft at 4am (2000 GMT) on Monday.
Only four miners have been found alive.
"At 8am, rescuers entered the mine to find the missing miners. There are 20 rescuers in the shaft right now, but the situation is unclear. We don't know what the situation is like down there," a man surnamed Hu at the mine's office said.
"There are eight to nine ambulances above ground waiting."
The chances of the missing miners surviving appear slim.
Survival rates in gas explosions are generally low due to the short time it takes for gas inhalation to kill a person, especially with high gas density.
"There are 20 rescuers in the shaft right now, but the situation is unclear. We don't know what the situation is like down there"
As the cause of the blast was under investigation, Xinhua reported separately that three miners died after a coal mine flooded in Yongzhou city in central China's Hunan province on 4 July.
Meanwhile, the State Administration for Work Safety also revealed that one miner died and 14 others were feared dead in a separate coal mine accident in southern China's Jiangxi province.
The accident happened on 7 July when the Yongsheng coal mine near Chishan township unexpectedly flooded, the state work safety agency said.
China's mines are considered the most deadly in the world, as safety is often sacrificed in the pursuit for the fossil fuel to drive the country's rapid industrialisation and economic growth.
The country relies on coal for two thirds of its energy needs and is not expected to shift significantly to other fuel sources for years to come.
Official figures show more than 6000 miners died in accidents in China last year, although independent estimates say the real figure could be as high as 20,000. Many fatalities occur in illegal mines.
Safety is often sacrificed in the
pursuit of fossil fuel
Reforms to the industry have often been promised, but enforcing the changes have proved the big stumbling block, mainly due to the profits that can be made, especially in industries such as coal-fired power plants, steel and cement.
The government has in the past ordered illegal or unsafe mines to shut and punished mine owners or local officials, but China's hunger for coal encourages owners to reopen mines illegally and officials to ignore the safety violations.
Investigations into the most deadly Chinese mine tragedy in recent years, which left 214 workers dead in February, blamed a disregard for worker safety by profit-focused operators.
Last month, China said it planned to limit the time coal miners have to spend at work underground to six hours a day in a bid to halt the trend of soaring fatalities.
Coal miners are currently made to work eight hours a day on average, with many forced to work overtime or when they feel the conditions are unsafe.
Critics, labour rights groups and miners have said the only way for the death toll to drop is to give workers rights, such as the right to insist on more safety and collective bargaining, which