Officials say they can't yet confirm the cause of what they are calling a "mass casualty event", or the number of people who were on board the trains.

相关官员称，他们还不能确认这场“重大灾难事件”的原因，也不能确认车上乘客的数量。

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There were 4, 229 people on board the vessel at the time of the casualty and while the tragic loss of life caused by this regrettable incident will rightly be the subject of forensic investigations for some time to come, it should not be forgotten that without the skilled response of the majority of the crew, the loss of life could have been far higher.

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