Delayed response

Relatives wait for news of missing family members outside the premises of Jilin Baoyuanfeng Poultry Co. [Photo by Wang Jing / China Daily]

The blaze was caused by a leak of liquid ammonia, which is used in the cooling system in meat-processing plants, according to Jilin province fire department on Monday.

However, Liu Changchun, mayor of Dehui, told China Youth Daily that the cause is still under investigation.

President Xi Jinping, on an official visit to the Americas and the Carribean, and Premier Li Keqiang urged intensive rescue efforts to minimize the number of casualties. They also called for a thorough investigation into the deadliest fire on the Chinese mainland since 2000, when 309 people died in a blaze at a nightclub in Henan province.

No matter what caused Monday's accident, the locked doors served to exacerbate the number of casualties, said Liu Yunbo, a 44-year-old survivor.

"There are about 300 workers in our department. Fearful that workers would stray from their posts, the managers normally only left one or two doors open and locked the rest. Most poultry processing factories do the same thing. We didn't realize the practice could be life-threatening," said Liu.

"I've been working in the plant for more than three years and know the department well. It has a giant gate, but only a small door that allows just two people to come out at the same time."

Just as Liu stepped out of the door, he was bowled over by terrified workers trying to get past. He sustained abdominal injuries as the crowd surged around him.

"I thought death was near. I held my breath and crawled for several meters before I fainted. When I came round several minutes later and saw lights I realized I was still alive," said Liu, speaking from his bed at Dehui Huikang Hospital.

Firefighters search for survivors in the ruins of the processing plant. [Photo by Wang Jing / China Daily]

The delayed response to the fire also contributed to the loss of life, a survivor called Shi told the Shanghai Evening Post.

"We heard there was a fire, but no one told us to evacuate. About 20 minutes later, the power was turned off. Everyone started trying to escape and some fell down. Twenty minutes later there was an explosion - the chances that those still inside could have survived are very slim," Shi told the newspaper.

According to Shi, five doors were opened when the fire broke out, but two remained locked.