Rescuers worked frantically Monday to try to find more than 150 workers trapped in a flooded coal mine being built in northern China, the latest disaster to hit the notoriously dangerous sector. President Hu Jintao and Premier Wen Jiabao have ordered authorities to go all- out to save the workers at the vast Wangjialing mine in Shanxi province, China's coal-producing heartland, where the accident took place on Sunday. The flood was the latest in a series of accidents plaguing China's coal mines, which are among the most dangerous in the world. More than 2,600 were killed in the country's collieries last year, according to official data. If the trapped workers are not rescued, the accident in Xiangning county will be the deadliest in China in more than four years. In November 2005, 171 workers died after an explosion in a mine in the country's northeast. Investigations so far have shown that 261 workers were in the Wangjialing pit as water started to gush in -- 108 were brought to safety, but 153 were still trapped underground, the nation's work safety administration said. 'I was so scared as I couldn't go forward anymore. Luckily there was an alleyway behind me... I just ran up from there, without thinking, and the water was chasing me,' survivor Fan Leisheng told state television. 'To survive down there around 1,000 metres underground would be very lucky.' A preliminary probe showed that water that had accumulated in nearby abandoned pits leaked into the new mine where the workers were located, it added. Dozens of police cars and ambulances were parked at the mine, which belongs to the state-owned Huajin Coking Coal company and covers an area of 180 square kilometres (70 square miles), an selfnews journalist saw. selfnews's reporting team was later asked to leave the premises. The company itself is half owned by China National Coal Group Corp, the second largest coal producer in the country and the parent of Hong Kong-listed firm China Coal Energy. 'Most of the trapped are migrant workers from Shanxi, Hebei, Hunan and Guizhou provinces,' a rescuer was quoted as saying by Xinhua news agency, referring to areas across a swathe of central China. There are currently 130,000 to 140,000 cubic metres of water in the pit, or the equivalent of at least 52 Olympic-sized swimming pools, state television reported. It will take more than a day to start lowering water levels and three days to completely drain the pit, although rescuers will be able to reach the workers before then, it added. In a small piece of good news, Xinhua said the water had stopped rising underground, adding to the workers' survival chances. Rescuers were using more than 10 pumps round-the-clock to drain the water, as rain fell in the area. Building at the mine kicked off in April 2007 but ran into problems because of complex geological conditions and difficulties in construction, media reports have said. It was scheduled to start production in October this year. The colliery, presented as a first-class model of safety and efficiency on Huajin's website, was due to produce six million tonnes of coal a year. Vice Premier Zhang Dejiang was immediately dispatched to the scene to oversee rescue efforts. Safety standards are often ignored in China's coal mines in the quest for profits and the drive to meet surging demand for coal -- the source of about 70 percent of the country's energy. In November, 108 miners were killed when an explosion ripped through a coal mine belonging to another state-owned firm in the northeastern province of Heilongjiang. And this month, 25 people died in a coal mine fire in Henan province. 