A distraught mother has been separated from her two-year-old boy when one of Sydney's new driverless trains took off from a station without her on board.
The toddler on Thursday afternoon travelled alone in his pram for more than 10 minutes after the doors of the Metro service separated the pair, leaving the mum stranded on the platform at Macquarie University station.
Bystanders and staff guarded the toddler until the train reached Epping station where the two-year-old was taken off the service.
The toddler was reunited with his distressed mother some 13 minutes after they were separated. She had travelled to Epping on the next service accompanied by a Metro staff member.
A Sydney Metro spokesperson told AAP the incident is being investigated and apologised for the distress caused.
AAP understands the train doors did not malfunction.
The Rail, Tram and Bus Union used Thursday's incident to call for design changes to imported trains including the multi-billion-dollar new intercity fleet from South Korea which is projected to roll out in 2020.
They say guard cabin doors on imported trains close at the same time as passenger doors preventing guards from seeing passengers as they board.
"Today's alarming incident on the Sydney Metro demonstrates exactly why automation needs to be moderated by human intervention," RTBU NSW secretary Alex Claassens said in a statement.
The $7.3 billion Sydney Metro has been plagued with problems since it began operating in May, with 30 reported incidents including train doors malfunctioning and urgent mechanical repairs and track work.
