At least 40 miners were killed and 11 others trapped in four separate coal mining accidents in China over the weekend, highlighting the country's struggle to improve mine safety.

Twenty-eight miners were confirmed dead following a fire that ignited suddenly at 8:10 pm on Saturday in a coal mine in Hancheng city, Shaanxi province, in Northwest China.

The Xiaonangou Coal Mine is a private enterprise, the owner of which is being held by police.

"The electrical supply cable caught fire and the miners were soon overcome by the fire and release of toxic gases," Gao Xiaoping, director of Hancheng city press office, told China Daily on Sunday.

Following the accident, Wu Dengchang, deputy governor of the province, immediately went to the scene accompanied by officials of the production safety and coal mine safety bureaus, as well as rescue experts from Xi'an, capital of the province, to direct and support the rescue effort.

"The bodies of five miners were located and brought out of the mine on Sunday morning," Gao said. "We expect the others will be found and recovered early on Monday."

According to Gao, the fire was still burning underground, and firefighters and rescue workers were doing everything they could to extinguish the blaze.

"The fire is expected to be put out late on Sunday and the bodies of the dead miners will be brought out as soon as possible," Gao said on Sunday.

"The aftermath of the disaster is being handled properly," Gao said. "We learned that 80 percent of the dead miners were migrant workers from other places and we are endeavoring to identify them."

The cause of the fire is under investigation.

The provincial government plans to hold a meeting on Monday to discuss production safety and arrange safety inspections of all coal mines in the province.