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For more on the factory explosion in Nanjing, we are joined on the phone by our reporter Li Zhen..
What caused the explosion?
1. Hello Li Zhen. Do authorities know what caused the explosion yet?
Is explosion affecting air quality?
2. Is air quality being affected by the explosion?
Ok, thanks for the update. That's our reporter Li Zhen in Nanjing with the latest on the factory explosion there.