'Sickening' footage shows teenager hanging off the side of Sydney train

Terrifying footage has laid bare the deadly game one Australian teenager played on a fast-moving Sydney train.

The chilling social media footage shows a young man clinging to the side of a train as it speeds through a rural area.

The death-defying stunt posted on Instagram has been condemned by Sydney train bosses after a tricky week of industrial action.

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The same group was seen engaging in similar dangerous antics at Meadowbank in north-west Sydney.

Videos shared online also reveal the teenagers messing around with train controls.

NSW transport boss John Murray said this type of behaviour could lead to certain death.

"Sadly this person's on the fast track to death or traumatic injury on the railway," he told 9News.

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"This video is nothing short of sickening for thousands of railway workers who spend their days trying to deliver a safe and reliable network."

Murray said there was "no doubt" these dangerous stunts were being performed and filmed simply to gain likes and views on social media.

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