HONG KONG – The Hong Kong government is investigating a fatal work accident in Chek Lap Kok that killed two men and seriously injured three others.

Three other workers felt unwell after inhaling methane gas at the construction site. They were also admitted to North Lantau Hospital for treatment and were in serious condition, reports said

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The accident happened at around 9 am on Wednesday when two workers fell into a manhole at a construction site on Chun Kwan Road. The duo was found unconscious when they were lifted out by firefighters, according to local media reports. They were certified dead after being sent to North Lantau Hospital.

Three other workers felt unwell after inhaling methane gas at the site. They were also admitted to the hospital for treatment and were in serious condition, reports said.

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The Labour Department said in a statement that they had immediately deployed staff to the scene upon receiving a report of the accident. An investigation into the cause of the accident is underway, it added.