A fire at a poultry plant in northeastern China trapped workers inside a cluttered slaughterhouse, killing at least 119 in one of China's worst industrial disasters in years despite recent work safety improvements.
Several dozen other people were hurt in the blaze in Jilin province's Mishazi township, which appeared to have been sparked by three early morning explosions, the official Xinhua News Agency said.
The provincial fire department attributed the blasts to an ammonia leak. The chemical is kept pressurised as part of the cooling system in meat processing plants.
The fire was one of China's worst recent industrial disasters, with the death toll the highest since a September 2008 mining cave-in that claimed 281 lives.
It was the third major industrial blaze to be reported in China in the past four days.
The two earlier fires were an oil tank explosion in Liaoning province that caused another oil tank to catch fire, killing two, and a blaze in a large granary in Heilongjiang province that wiped out 1000 tons of grain.
Monday's accident highlighted the high human costs of China's lax industrial safety standards, which continue to plague workplaces despite improvements in the country's work safety record in recent years.
Many of China's factories have sprung up in recent decades to drive the country's rapid economic growth, but accidents and chemical spills are common, often blamed on lax enforcement of safety rules and poor worker training.
The government has tightened checks on factories and mines to improve compliance with safety requirements, and deaths from workplace accidents fell nearly 5 percent last year from the previous year, according to Yang Dongliang, head of the State Administration of Work Safety.
Even in China's notoriously deadly coal mines, the death toll last year fell by more than 30 percent because of stricter management.
Monday's accident could also focus renewed scrutiny on China's biggest pork producer, Shuanghui International - unrelated to the poultry plant - as it aims to buy US food giant Smithfield in what would be China's biggest takeover of an American company.
Jason Yan, technical director in Beijing of the US Grains Council, said safety considerations usually take a backseat in China to features designed to maximize production and energy efficiency.
"I'm sure they consider some aspects of safety design. However, I think safety, to me, is not the first priority in their design plan," Yan said.
State media quoted survivors as saying it was difficult for workers to escape because only one door to the plant was open while other exits were locked and the fire spread quickly.
State broadcaster CCTV quoted unidentified workers as saying the fire broke out during a change of shifts when about 350 workers were at the plant, owned by Jilin Baoyuanfeng Poultry Co.
It wasn't clear how many workers had been accounted for and a provincial government media official, who refused to give his name, said he expected the death toll to rise further as more bodies were recovered from the charred building.
Some employees raised the alarm shortly after the shift began at 6 a.m., and then the lights went out, causing panic as workers rushed to find an exit, employee Wang Fengya told Xinhua.
"When I finally ran out and looked back at the plant, I saw high flames," Wang, 44, was quoted as saying. Xinhua said she and three other workers were sent to a hospital in the nearby provincial capital of Changchun.
Another worker quoted by Xinhua, 39-year-old Guo Yan, said the emergency exit at her workstation could not be opened and she was knocked to the ground in the crush of workers seeking to escape through a side door.
"I could only crawl desperately forward," Guo was quoted as saying. "I worked alongside an old lady and a young girl, but I don't know if they survived or not."
The newspaper Southern Metropolis Daily, known for its aggressive reporting, said the accident occurred in a factory building where chickens were being dismembered. The newspaper reported on its microblog that the fire spread rapidly, with industrial boilers exploding, and only a side door to the building was open with the rest of the exits locked.
It quoted an unidentified worker as saying the fire engulfed the building in three minutes, leaving too little time for many to flee.
The disaster killed 119 people, and 54 people were being treated in hospitals, the provincial government said on its microblog. Calls to fire and rescue services rang unanswered and hospital administrators said they had no information about the injured.
State media quoted hospital staffers as saying that most of the injured survivors were being treated for inhalation of toxic gases such as ammonia while others had burns of varying degrees.
By about noon, the fire had been mostly extinguished by about 500 firefighters, and bodies were being recovered from the charred buildings. CCTV footage showed dark smoke billowing up from the prefabricated cement structures topped with corrugated iron roofs.
Chinese President Xi Jinping and other top leaders ordered that no effort be spared to rescue and treat survivors as well as to investigate the cause of the incident.
It wasn't immediately clear if the workers were local residents or migrants from other areas.
The poultry plant is one of several in the area where chickens are slaughtered and then quickly cut up into pieces and shipped to market. The entire process takes place in near-freezing conditions and such plants are usually built with large amounts of flammable foam insulation to maintain a constant temperature.
Jilin Baoyuanfeng produces 67,000 tons of processed chicken per year and employs about 1200 people. The plant is located outside the city of Dehui, about 800 kilometres northeast of China's capital, Beijing.
Established in 2009, the company serves markets in 20 cities nationwide and has won numerous awards for its contribution to the local economy, according to introductions posted online.
The area where the fire occurred is an agribusiness centre, especially for poultry. Nearby is one of the biggest producers of broiler chickens in China, Jilin Deda Co, which is partly owned by Thailand-based conglomerate Charoen Pokphand Group.
Monday's fire hit a company that is much smaller than Jilin Deda. Though it's unlikely to have an impact on China's chicken supply, the accident came as chicken producers were seeing sales recover after an outbreak of a deadly new strain of bird flu, H7N9, briefly scared the public in April and early May.