Autopsies confirmed the boys, all street children about 10 years old, died from the deadly gas and ruled out death from injuries or strangling, Communist Party sources in Guizhou Province told China's official Xinhua News Agency.
Investigators in the mountain city of Bijie found burned charcoal in the trash container, which sources said led investigators to believe the boys had lit a fire inside it to keep warm.
Xinhua said the deaths created an Internet uproar among Chinese who chastised the local government and the boys' parents for negligence.
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