A gas explosion ripped through a coal mine in northern China on Sunday, killing at least 74 miners and trapping dozens, state media said. It was the country's deadliest coal mine accident in more than a year.

China's mines are the world's most dangerous with more than 3,000 deaths a year in fires, floods and explosions.

The pre-dawn blast occurred while 436 workers were in the Tunlan Coal Mine in Gujiao city near Taiyuan, the capital of Shanxi province, the official Xinhua News Agency said.

At least 74 miners died and 114 others were hospitalized, including six in critical condition, Xinhua said. It did not say how many workers remained trapped in the shaft but earlier reports said 65 were still underground.

Most of the injured miners were suffering from carbon monoxide poisoning, Xinhua said, citing doctors at a nearby hospital. Exposure to carbon monoxide, an odorless, colorless gas, can lead to death.

Xinhua said about 80 rescuers were searching for survivors.

State television CCTV showed rescuers in orange suits and red helmets with headlamps entering an elevator to be lowered into the mine shaft, while others emerged from the mine carrying workers on stretchers toward waiting ambulances.

A rescuer said in a phone interview with CCTV that some sections of the mine remained inaccessible to emergency teams because of high levels of carbon monoxide.

A rescued miner, Xue Huancheng, was quoted by Xinhua as saying while lying in a hospital bed that he remembered being ordered to flee because the ventilation system had broken down.

"At that time power supply underground was cut off and we had to walk," he said, adding that he fainted as he was about to reach the exit after walking about 40 minutes.

A State Administration of Work Safety duty officer who would only give her surname, Zhang, said the cause of the explosion was still being investigated.

The mine is owned by Shanxi Coking Coal Group, China's largest producer of coking coal, which is used in the production of steel. The company operates 28 mines.

The Tunlan mine has some of the best facilities in the country and had not reported any major accidents in the past five years, Xinhua said. It produces 5 million tons of coking coal a year.

The death toll was the highest in a coal mine accident since December 2007, when a gas explosion at a mine in Linfen city in Shanxi province killed 105 miners, according to the State Administration of Work Safety. That blast was triggered by an accumulation of gas in an unventilated tunnel.

The government has promised for years to improve mine safety, but energy-hungry China depends on coal for most of its power.

More than 1,000 dangerous small mines were closed last year, but the country's mining industry remains the world's deadliest. About 3,200 people died in coal mine accidents last year, a 15 percent decline from the previous year.

While China's overall coal mining safety record is abysmal, the numbers mask great disparities. Large, state-run mines tend to have safety records approaching those of developed countries while smaller mines have little or no safety equipment and weak worker training.

Government figures show that almost 80 percent of China's 16,000 mines are small, illegal operations.