A fire breaks out in a Chinese factory, and panicked workers discover one exit after another is locked. That describes not only the poultry plant fire that killed 119 people Monday, but a toy-factory blaze that left 87 workers dead 20 years earlier.

The similarities between the two worst factory fires in China's history suggest that little has changed for industrial workers even as the country has transformed its economy.

The bolted doors, clearly a violation of Chinese law, are emblematic of the often callous approach to worker safety in China that leads to frequent industrial disasters and an annual death toll in the tens of thousands.

While the country's increasingly sophisticated economy has surged into second place globally behind the United States, industrial safety conditions often more closely resemble those in struggling impoverished nations such as Bangladesh, where more than 1,100 people died in an April garment factory collapse.

"Throughout China's modern economic development, there has really been very little consideration for the rights and interests of the workers," said Li Qiang, executive director of New York-based China Labor Watch, which closely tracks working conditions in China.

Inspectors on Tuesday were combing through the charred wreckage of the Jilin Baoyuanfeng Poultry Co.'s processing plant, where fire raced through a chicken processing room in just three minutes on Monday morning.

It was one of China's worst recent industrial disasters. The death toll is the highest since a September 2008 mining cave-in that claimed 281 lives, and closely followed two other industrial blazes in the past five days that killed two workers.

Workers quoted in state media said exits were locked to secure the property and to keep them from stepping outside for breaks, despite the requirement in Article 24 of China's emergency response law requiring that safety exits be kept open and clearly marked. China's labor law also mandates safe working conditions.

Only a single door was open to permit escape. Workers trampled each other in the dark trying to get out.

The conditions closely resembled those at the Zhili toy factory in the southern city of Shenzhen where 87 young workers were killed in 1993. Exits at the toy factory also were locked, allegedly to prevent theft.

The Zhili factory's owners allegedly bribed inspectors to overlook safety violations, including putting the workers' dormitory, factory and warehouse all in the same building. The owners served brief prison sentences.

"The fact that the workers were locked inside in exactly the same way as 20 years ago ... shows that laws are not being enforced and inspections are not taking place," said Omana George of the Asia Monitor Resource Center, a worker advocacy group based in Hong Kong.

Initial reports said the poultry plant fire appeared to have been sparked by an explosion caused by leaking ammonia, a chemical kept pressurized as part of the cooling system in meat processing plants. The fire broke out during a shift change when about 350 workers were at the plant.

The plant's owner and managers have been taken into police custody while a special Cabinet investigation team looks into the causes of the disaster, according to state broadcaster CCTV and other Chinese media.

George said ensuring that exits are unlocked and unimpeded is the responsibility of local government safety officials. But she said they rarely bother to carry out checks and compliance is largely left to factory managers.

"The law requires a safe working place, but these employers are under little pressure to ensure that," George said.

China has a raft of laws on workplace safety, but they are often vague and enforcement is lax, said Geoffrey Crothall, spokesman for Hong Kong-based China Labor Bulletin, which also monitors industrial conditions.

He said that in addition, industrialists are often linked in a web of corruption and cronyism with local bureaucrats. Departments responsible for safety are frequently underfunded and enjoy little authority, Crothall added.

"In most cases, safety officials only get active after the fact. They have few real incentives to go out and find problems. They prefer to be inert," he said.

Jilin province, where the plant was located, has ordered a wide-ranging crackdown on fire safety violations and checks on mines and industries dealing with fireworks and dangerous chemicals.

Calls to the provincial police headquarters rang unanwered Tuesday. Phone lines at the provincial prosecutor's office and Jilin Baoyuanfeng's main offices rang constantly busy.

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 process takes place in near-freezing conditions and plants are usually built with large amounts of flammable foam insulation to keep temperatures constant.

Established in 2009, Jilin Baoyuanfeng produces 67,000 tons of processed chicken per year and employs about 1,200 people. It serves markets in 20 cities nationwide and has won numerous awards for its contributions to the local economy, according to online postings. The plant is located outside the city of Dehui, a poultry center about 500 miles (800 kilometers) northeast of China's capital, Beijing.

In addition to the 119 dead, several dozen people were being treated for burns and for inhalation of toxic gases such as ammonia.

Chinese workers have little power to demand safety improvements because they cannot effectively unionize. China has only one official Communist Party-controlled trade union, whose local branches work closely with officials and company management.

Chinese statistics show a gradual decline in the number of industrial accidents, but the death toll remains alarmingly high. The State Administration of Work Safety said worker deaths fell from 79,552 in 2010 to 75,572 in 2011, before dipping by another 5 percent last year.

The United States, which has a population less than one-quarter the size of China's, reports less than 5,000 work-related deaths per year.

The greatest improvements have come in China's notoriously deadly coal mining industry. The closure of the most dangerous small operations and better safety equipment helped annual fatalities drop 30 percent last year.

An increasingly vocal public is far from satisfied, however, with even the official Xinhua News Agency weighing in on the need for officials to be held accountable.

"Past investigations have shown that poor safety awareness and inadequate supervision caused many of the accidents, despite a repeated emphasis on work safety from the central government," it said in a Monday editorial. "The accidents are also the result of companies' desire to pursue profit at the cost of safety, as well as the laziness of officials who fail to fulfill their responsibilities."

Sentiment online was even more scathing, with many asking why inspections weren't carried out and preventative measures not taken. Writing on his Weibo account, Guangzhou-based current affairs commentator Li Huizhi said the act of locking the doors was dehumanizing.

"Is this a factory or a prison? Does management take these workers for people or poultry?" Li wrote.