YUZHOU, HENAN -An accident in a central China coal mine killed 21 miners Saturday and left another 16 trapped underground , the government said. The death rose to 26 Sunday morning as rescuers were battling to reach the 11 miners who were still trapped underground, rescue headquarters said. Rescuers were battling to reach the 11 miners still trapped underground, but chances for them to survive were very slim, said Du Bo, deputy chief of the rescue headquarters. "Based upon past experience, the remaining 11 miners could be buried in coal dust, so the survival chances are frail," Du said. More than 2,500 tons of coal dust smothered  the pit after the gas leak , which hampered  the rescue, said Du. The gas outburst happened at 6:03 a.m. Saturday when 276 miners were working underground in the mine in Yuzhou City. A total of 239 workers escaped but 21 were found dead and 16 trapped. An initial  investigation showed that 173,500 cubic meters of gas leaked out in the accident. Liu Wenbin, a deputy chief engineer of the company that owns the mine, was in the pit  when the accident happened. He organized the escape. "At around 6 a.m., I felt there was something wrong with the airflow in the shaft, and one of the team captains told me he also felt it and had already reported the problem," said Liu The mine is owned by Pingyu Coal & Electric Co. Ltd., a company jointly established by four investors, including Zhong Ping Energy Chemical Group and China Power Investment Corp. According to the writer, which of the following is not true?
The mine was owned by more than one company There was at least one more similar accident happening in Central China before Before the accident happened there was no sign of something wrong When the accident happened one of the mine owners was in the pit