Investigation underway after boy stranded on Adelaide train station platform

An investigation is underway after a six-year-old boy was left stranded on a train station platform in Adelaide.

The boy was travelling with his grandfather following an AFL match last Sunday when the duo disembarked at Elizabeth Station.

On realising the boy had left his hat on the train, his grandfather stepped back into the carriage to get it, when the doors closed behind him, The Advertiser reported.

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The grandfather, 65-year-old John Banbury, told The Advertiser he tried to push the button to open the door, while others pushed the emergency stop button and phoned police.

Banbury got off the train at Womma, the next stop, and police took him back to Elizabeth.

"This matter is under investigation by operator Keolis Downer Adelaide, who have advised that appropriate action, if necessary, will be taken once this process has been completed," A South Australia Department of Transport spokesperson said.

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"This incident was distressing for the child and his grandfather, and Adelaide Metro has contacted the family to apologise."

9news.com.au has contacted Downer Group and Keolis Downer Adelaide for comment.

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