Rescuers are close to the site of an underground fire that is just 200 meters from the place where 11 workers are trapped in Jiaxiang county in Jining, Shandong province, according to a news conference held on Wednesday afternoon.

The fire began in the coal mine on Tuesday night.

Four rescue teams involving 144 professional rescuers are working on reaching the trapped workers. Meanwhile, the teams have also been ventilating the mine, working to reduce the temperature and putting out the fire, according to Wang Duanwu, head of the Shandong Bureau of Coal Mine Safety Supervision, who spoke at the news conference.

Wang said rescue work has been hampered by the high temperature underground and the high concentration of poisonous gases like carbon monoxide.

Robots and other equipment are being used to extinguish the fire, and 8 metric tons of ice have been brought in to cool the area.

Party Chief of Shandong Liu Jiayi rushed to the mine site to oversee rescue work on Wednesday morning.

Liu said rescue efforts should follow scientific methods to ensure worker safety and prevent additional accidents from occurring.

The mine is owned by Liangbaosi Energy Co, affiliated with Feicheng Mining Group Co of Shandong Energy Group. Liangbaosi has over 95 square kilometers of coal mine area with a coal reserve of 569 million tons, according to Feicheng's website.

Liangbaosi was fined 40,000 yuan ($5,700) for violating related safety regulations on coal production in October, according to an enforcement notice released by the Shandong Bureau of Coal Mine Safety Supervision on Nov 12.

The bureau ordered the company to rectify and reform 10 problems related to coal production in October, including a ventilation problem.

The Ministry of Emergency Management released safety tips on Wednesday on its website to encourage coal production in accordance with laws and regulations and to promote caution while dealing with disaster-causing elements such as gas, water, fire and percussive ground pressure.

The ministry also urged related authorities to analyze coal production problems featured in the fourth quarter of the year and strengthen enforcement and supervision efforts to prevent further serious accidents.