Rescue workers and technicians are preparing to contain the bursting gas well early Friday morning to prevent further casualties in southwest China's Chongqing Municipality.

Rescue workers in red uniform, dozens of fire trucks and emergency equipment have already stood by as local police said reporters and other personnel would be denied access to the scene beginning 7:00 am Friday.

Authorities and technicians planned to carry out the blowout-containing program at about 10:00 am Friday after the China National Petroleum Corporation (CNPC), who operates the gas field, had worked out a detailed program.

"We will see whether we can curb the natural gas from further escaping three hours after the operation," said Qian Zhijia, deputy head of Chuandongbei gas field where the accident occurred.

The tragedy took place at 10:00 pm Tuesday and killed at least 191 people, when a well blew out suddenly and released a high concentration of natural gas and sulfurated hydrogen at Chuandongbei gas field in Kaixian County, some 337 kilometers northeast of Chongqing.

Chinese President Hu Jintao and Premier Wen Jiabao had sent their instructions on Thursday to local governments, urging relevant departments go all out to rescue victims, prevent poisonous gas from spreading further and reduce casualties.

Some 600 soldiers, armed police and fire fighters were mobilized to search for any survivors in the areas near the gas field.

It is feared that the number of casualties might rise, as 20 special teams continue combing the nearby areas for survivors and identifying casualties.

More than 41,000 people have been evacuated from areas within a radius of five km in the mountainous area around the gas field.

Some 290 people, mostly children, were hospitalized and four of them were still in critical condition while some 3,000 local people were reported to have suffered sulfurated hydrogen-caused symptoms like slight conjunctivitis and colds, according to local health bureau.

"We have admitted 138 patients poisoned by the toxic gas," said a doctor with the internal medicine department at Kaixian County People's Hospital.

"They have received timely and effective treatment and their conditions remain stable," the doctor said. "We are mainly using the antidotes medicine on the patients."

A total of 28 villages were hit by the gas blowout as local authorities had set up 15 shelter centers in schools and canteens for those evacuated.

"The county government has assembled quilts, biscuits and instant noodles for the victims," said She Mingzhe, Communist Party Secretary of Kaixian County.

In another development, CNPC technicians inflamed the blowout gas to curb further gas spread Thursday afternoon as the CNPC and local authorities tried to contain the burst, a spokesman for the CNPC told Xinhua.

"All citizens at our town had been evacuated," said an official at a rescue command office some one km from the gas blast scene.

Electricity supply to Gaoqiao Town, the hardest-hit area, had been cut off as hundreds of rescue workers rushed back and forth to arrange rescue materials.

"We have to evacuate immediately once our current gas density meters send out warning," a policeman told Xinhua at the scene.

"Though the gas has been ignited at the field, the gas spreading to the surrounding areas might be toxic to human at certain density," he said.

An investigation team dispatched by the State Administration of Work Safety had arrived at the blowout site at around 7:10 pm Thursday.

The gas field with a storage capacity of 50 to 60 billion tons of natural gas blew out suddenly and released a high concentration of natural gas and sulfurated hydrogen about 30 meters high, which quickly spread to nearby villages Tuesday night.

Earlier reports said the operations were going normally before the accident and gas suddenly exploded from the side of the drill when it went through the well 208 meters from the drill site.

The exact cause of the accident is still under investigation.

(Xinhua News Agency December 26, 2003)