TAIPEI - A chlorine gas leak at an Apple Inc. supplier's Chinese plant killed one person and left four others in comas, Xinhua Net reported late on Thursday.

Catcher Technology confirmed that an incident at its factory in Suzhou, eastern China, had caused injuries.

Xinhua reported the gas leak occurred during waste water processing.

Read more China coverage in our Behind The Wall blog

"It has nothing to do with our production or material used," James Wu, Catcher's vice president of corporate finance, told Reuters. "It happened when a contractor was processing waste; it was routine work. We are currently trying to understand what has gone wrong."

Wu did not confirm the number of the casualties or the nature of their injuries.

Worker at Apple supplier: 'We're humans, we're not machines'

The company later issued a statement, saying the accident involved five workers, though it also did not detail the nature of any injuries.

"The accident happened at the waste disposal facility and is not directly related to any manufacturing process, factory, or materials. This is also a single and isolated event," the statement said.

Worker suicide at Chinese plant of Apple supplier

Last October, a separate Catcher plant in Suzhou was ordered closed for a time because of complaints from nearby residents about strong odors from gas emissions.

Catcher Technology supplies metal casings for Apple Inc. and Dell Inc., the Wall Street Journal reported. 

The newspaper added:

China-based suppliers of electronic components for global brands have been under scrutiny in recent years following a spate of industrial accidents, pollution charges and employee suicides.

In one example of how international firms have addressed such issues, Apple is working with major supplier Foxconn Technology Group, which makes iPhones and iPads, to improve conditions at its factories in China after an audit report found excessive working hours and health and safety issues there. 

Reuters contributed to this report.

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