About 50 workers were inside the factory south of Phnom Penh, the capital, when the ceiling caved in, said police officer Khem Pannara. He said heavy iron equipment stored on the floor above appeared to have caused the collapse.
Two bodies were pulled from the wreckage and seven people were injured, he said. Rescuers combed through rubble for several hours and after clearing the site said that nobody else was trapped inside.
At a clinic where she was being treated for her injuries, worker Kong Thary cried on the telephone as she recounted the collapse.
"We were working normally and suddenly several pieces of brick and iron started falling on us," the 25-year-old said.
An initial investigation showed the ceiling that collapsed was poorly built and lacked the proper building materials to support heavy weight, said Ou Sam Oun, governor of Kampong Speu province, where the factory was located.
Chea Muny, chief of a trade union for factory workers, identified the factory as a Taiwanese-owned operation called Wing Star that produces sneakers for Asics, a Japanese sportswear label. He said shoes made at the factory were imported to the United States and Europe.
An Asics spokeswoman in Tokyo confirmed the factory was in contract to make Asics running shoes. She said Asics was trying to determine what happened.
"We understand that some people have died, so first we offer our condolences," said spokeswoman Masayo Hasegawa in Tokyo. She said she did not have information on the last time the building structure had been inspected but added, "We want the highest priority to be placed on saving lives."
The factory complex, which opened about a year ago, consists of several buildings and employs about 7,000 people, said Pannara, the police officer. The structure where the collapse occurred was mainly used as a storage warehouse for shoe-production equipment but had a small work area for about two dozen people, Chea Muny said.
The garment industry is Cambodia's biggest export earner, employing about 500,000 people in more than 500 garment and shoe factories. In 2012, the southeast Asian country shipped more than $4 billion worth of products to the United States and Europe.
The accident comes about three weeks after a building collapse in Bangladesh killed 1,127 people in the global garment industry's deadliest disaster.
"This shows that the problem is not only isolated to Bangladesh, and that companies (elsewhere) are trying to drive prices down by taking shortcuts on workers' safety," said Phil Robertson of Human Rights Watch.
The report by the International Labor Organization found "a worrying increase in fire safety violations," including that only 57 percent of factories kept paths free of obstructions. It reported "unacceptable" heat levels, abuse of overtime hours and a lack of worker access to drinking water.
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