HARBIN — Six workers have been confirmed dead after they were hit by a freight train in northeast China's Heilongjiang province on Tuesday morning, according to China Railway Harbin Bureau Group Co, Ltd.

The accident occurred around 1:55 am when the workers were on the track of a railway section in the outskirt of Jiamusi City, sources with the company said.

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Two of them died on the spot, while the other four died after rescue efforts failed.

The cause of the accident is not known yet, and the investigation continues.