"The train slowed down abruptly, the lights went off, and then there was a spark of fire and smoke. We were blocked in," one passenger told Russian TV.

一名乘客对俄罗斯电视台说：“列车突然减速，灯灭了，然后是火花和烟雾，我们被堵在车里了。”

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The train appeared, smoke billowing from the funnel of the engine.

火车开来了，车头的烟囱里冒出滚滚浓烟。

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Smoke rises from the engine as the train climbs a hill.

当火车向着山上爬行时，烟从机车上冉冉升起。

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"We could hear all the sirens and you could smell the smoke as the train went past the site, " he said in a submission to CNN's iReport.

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The danger was compounded by an overhead power cable, which broke loose and fell on the roof of the rear car, causing further arcing and a large amount of smoke inside the train.

BBC: Metro train fire

And the lights went off and smoke started filling the train car.

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