The Department of Infrastructure says it's investigating after a tram's brake failed on Snaefell.
The incident happened on Friday, while passengers were on board - the tram ran backwards 200 yards before mechanical brakes kicked in.
The DOI says it's now working with the Island's Health and Safety at Work Inspectorate.
In a statement, the department says the matter is being treated very seriously and it's committed to ensuring the safety of passengers and crews.
It adds it won't be commenting further while the investigation continues.
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